Iyayi, I. E., & Ajaja, O. P. (2026). Effect of Inclusive Teaching Strategy on Senior Secondary School Chemistry Students’ Achievement in Edo Central Senatorial District. International Journal of Research, 13(1), 225–245. https://doi.org/10.26643/ijr/2026/3
Iyayi, Innocent Ehighae
Department of Science Education
Faculty of Education, Delta State University, Abraka, Nigeria
Ajaja, Osawaru Patrick
Department of Science Education
Faculty of Education, Delta State University, Abraka, Nigeria
Abstract
The main purpose of this study was to examine the effect of Inclusive Teaching Strategy (ITS) on senior secondary school chemistry students’ academic achievement in Edo Central Senatorial District of Edo State. The design adopted for this study was the 2×2 factorial pretest–posttest non-equivalent group planned variation quasi-experimental design. The sample comprised 366 SSII chemistry students drawn from six public secondary schools using simple random sampling technique. Students were taught selected chemistry concepts using Inclusive Teaching Strategy and the Lecture Method. The Chemistry Achievement Test (CAT) was used for data collection and it yielded a reliability coefficient of 0.72 using Kuder-Richardson Formula 21 statistics (KR-21). Data were analyzed using mean, standard deviation, paired sample t-test, independent sample t-test, and Analysis of Covariance (ANCOVA). Findings showed that (i) students taught with Inclusive Teaching Strategy achieved significantly higher mean scores than those taught with the lecture method;(ii) no significant difference was found between male and female students taught with Inclusive Teaching Strategy, and (iii) no significant interaction effect was observed between teaching method and sex on achievement. The study concludes that Inclusive Teaching Strategy is an effective and sex-neutral approach for improving achievement in chemistry and recommends that chemistry teachers at the senior secondary school level should adopt Inclusive Teaching Strategy in classroom instruction to enhance students’ academic performance.
Keywords: Inclusive Teaching Strategy, Chemistry Achievement, Lecture Method, Sex, Secondary School.
1.Introduction
Chemistry is a core science subject that provides learners with an understanding of the composition, structure, properties, and transformation of matter. The subject plays a significant role in scientific and technological development and requires students to engage in critical thinking, conceptual analysis, and interpretation of complex relationships among chemical principles (Okebukola, 2015; Taber, 2014). Many chemistry concepts, such as chemical equilibrium, energy changes, and reaction processes, are inherently abstract and cognitively demanding, making them difficult for learners to understand, especially when instruction is not sufficiently supportive of conceptual understanding (Taber, 2014). Chemistry learning extends beyond memorization of facts and formulas; it involves constructing meaning from concepts and applying knowledge to new and unfamiliar situations (Okebukola, 2015).
When instructional methods do not align with students’ preferred ways of learning, understanding becomes more challenging. Some learners require opportunities to visualize concepts, manipulate materials, discuss ideas, and actively participate in learning activities before achieving deep understanding (Taber, 2014). Consequently, recognizing learner diversity and adapting instructional delivery to support different learning needs remains an important concern in education (UNESCO, 2020; National Commission for Persons with Disabilities [NCPWD], 2024). This concern is particularly significant in chemistry education, where abstract concepts and symbolic representations often pose learning challenges for students.
The lecture method is one of the most widely used instructional strategies in Nigerian secondary schools. It allows teachers to cover large portions of the curriculum and provides structured, linear explanations of chemistry content. Through teacher-led presentations, the method supports content organization and note-taking (Ajaja, 2013; Aina&Sofowora, 2020). However, because lecture-based instruction relies largely on verbal explanation, its effectiveness may vary among learners with different learning preferences. This has created the need to examine the lecture method alongside alternative instructional approaches that seek to accommodate learner diversity. One strategy that has this characteristic is the Inclusive Teaching Strategy (ITS).
Inclusive Teaching Strategy (ITS) is an instructional approach that integrates visual, auditory, kinesthetic, and collaborative learning opportunities within the same lesson. Visual representations support learners who process information pictorially and help reduce the abstract nature of chemistry concepts (Permatasari et al., 2022). Auditory approaches, such as teacher explanations and guided discussions, support students’ understanding through verbal processing (Mayer, 2020).Kinesthetic learning, through hands-on laboratory activities and physical engagement with materials, enables learners to actively construct understanding of scientific concepts (Ojonugwa et al., 2023), while collaborative activities encourage peer interaction and shared inquiry (Ajaja&Eravwoke, 2010). By incorporating multiple learning modes, Inclusive Teaching Strategy is designed to address variations in how students engage with and understand chemistry concepts (Mayer, 2020; Permatasari et al., 2022).
One major advantage of Inclusive Teaching Strategy is its ability to reduce the abstractness of chemistry concepts by presenting content through multiple representations and learning experiences. By combining visual aids, verbal explanations, hands-on activities, and peer interaction, Inclusive Teaching Strategy makes learning more concrete, meaningful, and accessible to a wide range of learners. The strategy promotes active participation, increases learner engagement, and supports deeper conceptual understanding by allowing students to interact with content in ways that align with their learning preferences. Inclusive Teaching Strategy also fosters collaboration, communication skills, and learner confidence, creating a supportive classroom environment where students feel encouraged to contribute and learn from one another. These advantages position Inclusive Teaching Strategy as a flexible and learner-responsive approach capable of supporting improved learning outcomes in chemistry.
The effectiveness of an instructional strategy is reflected in students’ achievement. Achievement in chemistry refers to the measurable learning outcomes students demonstrate after instruction, often assessed through tests or performance tasks (Taber, 2014; OECD, 2019). Improving students’ achievement in chemistry remains a key educational goal, particularly in contexts where persistent difficulties in understanding abstract concepts have been reported (Hattie, 2012; Taber, 2014; OECD, 2019). Given the need to improve learning outcomes through instructional approaches that recognize learner diversity, this study investigates the effects of Inclusive Teaching Strategy on senior secondary school students’ achievement in chemistry in Edo Central Senatorial District of Edo State.
2. Literature Review
Inclusive Teaching Strategy (ITS) is a learner-responsive instructional approach designed to accommodate students’ diverse learning needs through the deliberate integration of multiple instructional modalities (Alquraini&Rao, 2020; Rao et al., 2014). Grounded in the Universal Design for Learning (UDL) framework developed by Rose and Meyer, Inclusive Teaching Strategy emphasizes instructional flexibility by providing multiple means of representation and engagement to support learners’ varied ways of processing information (Rose & Meyer, 2002; CAST, 2018). The strategy recognizes that students differ in how they access, interpret, and apply knowledge, and that instruction should be structured to reduce learning barriers and promote equitable access to understanding (UNESCO, 2020).
In chemistry education, where many concepts are abstract and cognitively demanding, differences in learners’ ways of engaging with content become particularly important. Inclusive Teaching Strategy responds to this challenge by integrating visual, auditory, kinesthetic, and collaborative approaches within the teaching of the same concept (Bethel-Eke &Eremie, 2017; Ajaja & Eravwoke, 2010). Visual representations such as diagrams, charts, models, and animations help learners make sense of invisible chemical processes and relationships (Mudaly& Singh, 2016). Auditory explanations, guided questioning, and classroom discussions support conceptual clarification by allowing learners to articulate and refine their understanding through verbal interaction (Njoku&Abdulhamid, 2016). Kinesthetic activities, including laboratory experiments and hands-on tasks, enable learners to interact directly with chemical materials and phenomena, thereby strengthening conceptual understanding through experience (Mudaly& Singh, 2016). Collaborative learning further provides opportunities for peer discussion, shared problem solving, and meaning construction, allowing students to learn from one another in a supportive environment (Ajaja&Eravwoke, 2010). The combined use of these approaches enables learners to access chemistry concepts through complementary pathways that promote deeper conceptual understanding and meaningful learning (Adom et al., 2023).
Academic achievement in chemistry reflects students’ ability to understand, retain, and apply chemical concepts following instruction. Given the abstract nature of the subject, achievement is strongly influenced by how well instructional methods support conceptual understanding and knowledge application. Teaching approaches that provide opportunities for visualization, experiential engagement, and discussion can enhance students’ ability to interpret relationships among chemical concepts and apply them effectively.
Empirical evidence indicates that inclusive and multimodal instructional practices positively influence students’ academic achievement. Studies have shown that learners taught using multiple representations demonstrate significantly higher achievement than those taught using conventional instructional approaches. In particular, Mudaly and Singh (2016) found that students exposed to verbal, graphical, symbolic, and practical representations developed deeper conceptual understanding and improved problem-solving ability in chemistry. Similarly, research grounded in Universal Design for Learning (UDL) principles indicates that flexible instructional designs enhance academic outcomes by allowing learners to access content in ways that align with their cognitive strengths and learning preferences (Alquraini&Rao, 2020). These findings suggest that instructional approaches that deliberately integrate multiple modes of learning are more effective in promoting meaningful understanding and academic success.
Despite growing evidence supporting inclusive instructional practices, the literature reveals a clear gap. Most existing studies focus on single modalities or isolated inclusive practices rather than the simultaneous integration of visual, auditory, kinesthetic, and collaborative strategies within the same instructional sequence. In addition, limited research has examined the application of such a fully integrated Inclusive Teaching Strategy in chemistry classrooms, particularly in relation to students’ academic achievement. This suggests the need for a similar study in chemistry, a gap addressed by this study.
Research Questions
There following research questions were raised to guide this study
- What is the difference in the achievement of chemistry students taught with Inclusive Teaching Strategy and those taught with the Lecture Method?
- What is the difference in the achievement of male and female students taught using Inclusive Teaching Strategy?
- What is the interaction effect between teaching methods and sex on chemistry students’ achievement?
Research Hypotheses
H01: There is no significant effect of inclusive teaching strategy and lecture method on the academic achievement of secondary school chemistry students.
H02: There is no significant difference in the achievement of male and female students taught using Inclusive Teaching Strategy.
H03: There is no significant interaction effect between teaching methods and sex on chemistry students’ achievement.
Research Objectives
The main objective of the study was to determine the effect of Inclusive Teaching Strategy on Senior Secondary School Chemistry Students’ Achievement in Edo Central Senatorial District in Edo State.
4. Research Methodology
4.1 Research Design
The study adopted a 2×2 factorial pretest–posttest non-equivalent control group planned variation quasi-experimental design. The study involved two instructional methods; Inclusive Teaching Strategy and the Lecture Method, sex (male and female), and repeated testing (pretest and posttest). In this design, subjects were not randomly assigned to experimental and control groups; rather, intact classes were used for the study. The variables of the study included instructional strategies (Inclusive Teaching Strategy and Lecture Method) as the independent variables, academic achievement as the dependent variable, and sex (male and female) as the moderating variable. The use of intact classes made randomization impracticable, as students were already organized into existing classroom groups within their schools.This design was considered appropriate because it allowed for the comparison of students’ achievement before and after exposure to the instructional strategies while maintaining the natural classroom setting. According to Johnson and Christensen (2000), any research design in which random assignment; a fundamental requirement of true experimental design is omitted is classified as a quasi-experimental design. The pretest–posttest non-equivalent control group design therefore provided a suitable framework for examining the effect of Inclusive Teaching Strategy on chemistry students’ achievement while controlling for initial differences between groups through pretesting.
4.2 Population and Sampling
The population for the study consisted of thirteen thousand, two hundred and eighty (13,280) Senior Secondary School II (SSII) chemistry students in all public secondary schools in Edo Central Senatorial District of Edo State in the 2025/2026 academic session. Edo Central Senatorial District comprises five Local Government Areas and several public secondary schools offering chemistry at the senior secondary level (Edo State Ministry of Education, 2025).The sample for the study consisted of three hundred and sixty-six (366) SSII chemistry students drawn from six public secondary schools randomly selected from three Local Government Areas within Edo Central Senatorial District. Two schools were selected from each of the three Local Government Areas, making a total of six schools. Six chemistry teachers and six intact SSII chemistry classes constituted the sample for the study.
The sampling technique used in the selection of the Local Government Areas, schools, and classes was stratified random sampling and simple random sampling (balloting). To achieve this, all five Local Government Areas in Edo Central Senatorial District were listed, and three were selected using the balloting method without replacement. Thereafter, all public secondary schools in each selected Local Government Area were listed separately. From each Local Government Area, two schools were randomly selected through balloting to obtain the required six schools. In schools with more than one SSII chemistry class, one intact class was selected using simple random sampling. Intact classes were used to avoid disruption of normal school activities. Only public secondary schools were used because they operate under similar conditions, follow the same curriculum, and are supervised by a central authority, the Edo State Ministry of Education, thereby ensuring uniformity in learning environment.
4.3 Research Instrument
The instrument for data collection was the Chemistry Achievement Test (CAT). The test was designed to measure senior secondary school students’ achievement in chemistry after exposure to the instructional treatments. The Chemistry Achievement Test was made up of two sections, Sections A and B. Section A contained items on the bio-data of the students, such as sex and school. Section B consisted of fifty (50) multiple-choice items drawn from West African Senior School Certificate Examination (WASSCE) past questions (2018–2024) based on the chemistry concepts taught during the study. Each item had four options (A–D) with one correct answer and three distractors.Each correct answer in Section B attracted two marks, while incorrect answers attracted zero mark, giving a maximum obtainable score of 100 marks. In answering the research questions and testing the hypotheses, only the total scores obtained from Section B of the CAT were used. The instrument was administered twice: as a pre-test before the treatment and as a post-test after the treatment.
4.3.1 Validity and Reliability of Research Instrument
The face validity of the Chemistry Achievement Test was determined by three experts: one Science Educator, one expert in Chemistry Education, and one expert in Measurement and Evaluation. The experts examined the CAT alongside the research questions and hypotheses to ascertain whether the instrument could adequately generate data capable of answering the research questions and testing the stated hypotheses. Based on their observations, minor corrections were suggested and effected, after which the instrument was approved for use.
The content validity of the CAT was established using a table of specifications based on Bloom’s taxonomy of educational objectives, which ensured adequate representation of content areas and cognitive levels. The table showed that the test items were appropriately distributed across knowledge, comprehension, application, and synthesis levels, confirming that the instrument sufficiently covered the content taught during the study
Table 1
Table of Specification of a 50 items CAT based on Bloom’s taxonomy (1956)
| Content | Knowledge 36% | Comprehension 24% | Application 24% | 16% | Total % of items |
| The Periodic Table (18%) | 4 | 2 | 2 | 1 | 9 |
| Energy and Chemical Reaction (18%) | 3 | 2 | 2 | 1 | 8 |
| Mass Volume Relationship in Reactions (16%) | 3 | 2 | 2 | 1 | 8 |
| Volumetric and Qualitative Analysis (14%) | 2 | 2 | 2 | 2 | 8 |
| Acid, Base Reaction (18%) | 3 | 2 | 2 | 1 | 8 |
| Water, Solutions and Solubility (16%) | 3 | 2 | 2 | 2 | 9 |
| Total | 18 | 12 | 12 | 8 | 50 |
To determine the construct validity of the instrument, the difficulty level of each item was determined using the item difficulty index formula by dividing the number of students who answered each item correctly by the total number of students who attempted the item. The difficulty indices ranged between 0.00 and 1.00. According to Wiseman (1999) and Ajaja (2013), items with indices between 0.30 and 0.70 are considered appropriate. All items selected from the WASSCE past questions met this criterion and were therefore retained.
To establish reliability of the instrument, a trial testing of the instrument was carried out on twenty four (24) SSII chemistry students from a school that was not part of the study sample but possessed similar characteristics, such as exposure to the same SSII chemistry curriculum and a similar learning environment. The data obtained from the trial testing were analyzed using the Kuder–Richardson Formula 21 (KR-21) reliability statistic, which is appropriate for dichotomously scored test items. The analysis yielded a reliability coefficient of 0.72, indicating that the Chemistry Achievement Test was sufficiently reliable for use in the study. According to Nunnally& Bernstein (1994), a reliability coefficient of 0.70 and above is considered acceptable for educational research instruments.
4.4 Treatment Procedure
Step I: Training of the Teachers Used for Inclusive Teaching Strategy and Lecture Method Groups
Before the commencement of the treatment, teachers who served as research assistants were trained on the instructional strategies assigned to their respective groups.
4.4.1 Inclusive Teaching Strategy Group
Teachers assigned to the Inclusive Teaching Strategy (ITS) group were trained for two days using a specially prepared instructional guide developed by the researcher. On Day One, the teachers were introduced to the concept of Inclusive Teaching Strategy, its theoretical foundation based on the Universal Design for Learning (UDL) framework, and the advantages of using inclusive instructional approaches in chemistry teaching. The training emphasized the integration of visual, auditory, kinesthetic, and collaborative strategies within a single chemistry lesson to address diverse learners’ needs. On Day Two, the teachers were trained on the practical implementation of Inclusive Teaching Strategy in the classroom. The researcher demonstrated how to integrate the four instructional approaches simultaneously while teaching selected chemistry concepts. Teachers were then given the opportunity to practice lesson delivery using the strategy under the supervision of the researcher. The training session ended after the researcher was satisfied that the teachers had adequately mastered the steps involved in applying the Inclusive Teaching Strategy.
Steps Followed in Teaching Using Inclusive Teaching Strategy (ITS)
During the treatment period, teachers in the Inclusive Teaching Strategy group taught chemistry concepts using the following steps:
Introduction of the Concept:
The teacher introduced each lesson by asking questions to elicit students’ prior knowledge related to the topic. This helped to identify students’ existing conceptions and prepared them for new learning.
Application of Visual Strategy:
The teacher used visual instructional materials such as diagrams, charts, illustrations, videos, and chemical models to explain abstract chemistry concepts and enhance students’ understanding.
Application of Auditory Strategy:
Clear verbal explanations were provided, supported by guided discussions and questioning. Students were encouraged to listen, respond, and ask questions to reinforce understanding through auditory interaction.
Application of Kinesthetic Strategy:
Students were engaged in hands-on activities such as experiments, demonstrations, and manipulation of instructional materials to promote learning through physical involvement.
Application of Collaborative Strategy:
Students were organized into small groups for peer discussion, cooperative problem-solving and group-based activities that encouraged interaction, idea sharing, and collective learning.
Evaluation:
The teacher assessed students’ understanding by asking oral questions and allowing students to ask questions. Feedback was provided to correct misconceptions and strengthen learning.
Summary:
The teacher concluded the lesson by summarizing key points and linking them to the activities carried out during the lesson.
4.4.2. Lecture Method Group Teachers
Teachers assigned to the Lecture Method group were trained briefly on how to use the conventional lecture method for teaching chemistry. During the training session, the teachers were exposed to the basic steps involved in lecture-based instruction, including lesson introduction, explanation of concepts, questioning, and lesson summary. They were instructed to teach using the lecture method without incorporating inclusive instructional components.
Steps Followed in Teaching Using the Lecture Method
During the treatment period, teachers in the Lecture Method group taught chemistry concepts using the following steps:
Introduction of the Lesson:
The teacher introduced the lesson by asking a few questions to assess students’ prior knowledge related to the topic.
Explanation of Concepts:
The teacher explained the chemistry concepts orally while students listened and took notes. The explanation followed a structured and sequential presentation of content.
Evaluation:
The teacher asked questions during and after the explanation to assess students’ understanding of the lesson. Students responded individually.
Summary of the Lesson:
The teacher summarized the lesson by restating the main concepts taught and emphasizing important points.
Step II: Pre-testing of the Groups
One week before the commencement of the treatment, students in both the Inclusive Teaching Strategy group and the Lecture Method group were administered the Chemistry Achievement Test (CAT) as a pre-test. The test was administered under uniform conditions and the completed scripts were collected after One hour. The pre-test scripts were scored and recorded to determine the equivalence of the groups before the treatment.Immediately after the pre-test, the researcher distributed detailed instructional guides on the use of Inclusive Teaching Strategy and Lecture Method to the respective teachers. The teachers were instructed to strictly adhere to the procedures outlined in the guides throughout the treatment period.
Step III Post-testing
At the end of the treatment period, which lasted for six weeks, a post-test was administered to students in both the Inclusive Teaching Strategy group and the Lecture Method group using the Chemistry Achievement Test (CAT). The post-test was administered under the same conditions as the pre-test, and the scripts were collected, scored, and collated for data analysis.
5. Research Results and Discussion
5.1 Research Results
Research Question 1: What is the difference in the achievement of chemistry students taught with Inclusive Teaching Strategy and those taught with the Lecture Method?
Table 1
Descriptive statistics of mean and standard deviation showing the mean scores of chemistry students taught with inclusive teaching strategy and lecture method
_______________________________________________________________________
Methods N Mean Mean DiffSD
Inclusive Teaching 190 73.96 14.77 13.21
Lecture Method 176 60.75 13.85
Table 1 shows that students taught with inclusive teaching strategy obtained a mean score of 73.96 with a standard deviation of 14.77 at posttest. While those taught with lecture method, obtained a mean score of 60.75 with a standard deviation of 13.85 at posttest. From the means, it can be seen that there exist a mean difference of 13.21, in favour of the inclusive teaching strategy group. To determine if the difference is significant, an independent sample t-test statistics was used to test hypothesis one.
H01: There is no significant difference in the mean scores of chemistry students taught using inclusive teaching strategy and lecture method
To determine the appropriate statistics to test hypothesis one, independent sample t-test statistics was used to analyze the data at pre-test and the result is shown in Table 2.
Table 2
Independent samplest-test statistics comparing the pretest mean scores of chemistry students taught with inclusive teaching strategy and lecture method.
________________________________________________________________________
Methods N Mean Mean Diff SD tcal df Sig (2-tail)
Inclusive Teaching 190 29.37 12.81
2.50 1.87 364 0.062
Lecture Method 176 26.87 12.68
________________________________________________________________________
Table 2 shows that there is no statistically significant difference in the pretest mean achievement scores of chemistry students taught using Inclusive Teaching Strategy and those taught using the Lecture Method, t(364) = 1.87, p = .062. Since the p-value is greater than the 0.05 alpha level of significance, the difference is not significant. This indicates that the two groups were comparable in achievement before the treatment.
Table 3. Independent sample statistics comparing the mean scores of Chemistry students taught with inclusive teaching strategy and lecture method at post-test
| Methods | N | Mean | SD | Mean Diff | t-cal | df | Sig. (2-tailed) |
| Inclusive Teaching | 190 | 73.96 | 14.77 | ||||
| Lecture Method | 176 | 60.75 | 13.85 | 13.21 | 8.81 | 364 | < .001 |
Table 3 shows that the difference is statistically significant since the p-value is less than .001, which is lower than the 0.05 alpha level of significance. Therefore, Hypothesis One, which states that there is no significant difference in the mean scores of chemistry students taught using Inclusive Teaching Strategy and the Lecture Method, is rejected.
Research Question Two: What is the difference in the mean scores of male and female chemistry students taught using inclusive teaching strategy?
Table 4
Descriptive statistics of mean and standard deviation showing the mean scores of male and female chemistry students taught with inclusive teaching strategy
________________________________________________________________________
Methods N Mean Mean Diff SD
Male 89 74.40 15.64
0.84
Female 101 73.56 14.02
Table 4 is a descriptive statistics showing that male students taught using Inclusive Teaching Strategy obtained a slightly higher mean achievement score (M = 74.40, SD = 15.64) than female students (M = 73.56, SD = 14.02), with a mean difference of 0.84 in favour of the males. An independent samples t-test was conducted to determine whether this observed difference was statistically significant.
H02: There is no significant difference in the achievement of male and female students taught using Inclusive Teaching Strategy.
Table 5
Independent sample t-test statistics comparing the mean scores of male and female chemistry students taught with inclusive teaching strategy
________________________________________________________________________
Methods N Mean Mean Diff SD tcal df Sig (2tail)
Male 89 74.40 15.64 0.84 0.39 187 0.697
Female 101 73.56 14.02
Table 5 shows that the difference is not statistically significant since the p-value (p = .697) is greater than the 0.05 alpha level of significance. Therefore, Hypothesis Two, which states that there is no significant difference in the mean scores of male and female chemistry students taught using Inclusive Teaching Strategy, is not rejected.
Research Question Three: What is the interaction effect between methods and sex on chemistry students’ achievement?
Table 6
Descriptive statistics of mean and standard deviation showing the interaction effects of methods and sex on chemistry students’ achievement
________________________________________________________________________
Methods Sex N Mean Mean Diff SD
Inclusive Teaching 190 73.96 14.77 13.21
Lecture Method 176 60.75 13.85
________________________________________________________________________
Male 89 74.40 15.64
Inclusive Teaching 0.80
Female 101 73.56 14.02
________________________________________________________________________
Male 83 59.20 13.97
Lecture Method
2.92
Female 93 62.13 13.27
In Table 6, the descriptive statistics indicate that students taught using Inclusive Teaching Strategy achieved higher post-test mean scores (M = 73.96, SD = 14.77) than those taught using the Lecture Method (M = 60.75, SD = 13.85), with a mean difference of 13.21 in favour of the Inclusive Teaching Strategy. Within the Inclusive Teaching Strategy group, male students recorded a slightly higher mean score (M = 74.40, SD = 15.64) than female students (M = 73.56, SD = 14.02), though the mean difference was minimal (0.80). In the Lecture Method group, female students obtained a higher mean score (M = 62.13, SD = 13.27) than male students (M = 59.20, SD = 13.97), with a mean difference of 2.92. These variations suggest differences in achievement across methods and sex; however, Analysis of Covariance was used to determine whether the observed interaction effect was statistically significant.
H03: There is no significant interaction effect between teaching methods and sex on chemistry students’ achievement
Table 7
Analysis of Covariance statistics comparing the effect of interaction between method and sex on achievement.
______________________________________________________________________________
Source Type III sum of square df mean square F Sig
Corrected model 73931.125 4 18482.781 397.438 0.00
Intercept 82151.832 1 82151.832 1766.525 0.00
Pre-achievement 57584.021 1 57584.021 1238.233 0.00
Groups 17229.838 1 17229.838 370.496 0.00
Sex 3.626 1 3.626 0.078 0.780
Group*Sex 1.781 1 1,781 0.038 0.845
Error 16788.219 361 46.505
Total 1763576.00
Corrected total 90719.344 365
Table 7 shows that the observed interaction effect is not significant since the calculated significant value of 0.845 which is higher than the critical significant value of 0.05 was obtained. With this H03which states that there is no significant effect of interaction between method and sex on achievement is not rejected.
5.2. Discussion of Findings
This study examined the effect of Inclusive Teaching Strategy and the Lecture Method on senior secondary school students’ achievement in chemistry, with particular attention to differences across instructional methods and sex, as well as their interaction effects. The findings are discussed in line with the research questions and supported by relevant empirical studies.
The first finding of the study showed that students taught using Inclusive Teaching Strategy achieved significantly higher post-test mean scores than those taught using the Lecture Method. Although both instructional approaches led to improvements in students’ achievement, the magnitude of improvement was greater for students exposed to Inclusive Teaching Strategy. The significant mean difference in favour of Inclusive Teaching Strategy indicates that the strategy was more effective in enhancing students’ achievement in chemistry than the Lecture Method. This superior performance may be attributed to the multimodal nature of Inclusive Teaching Strategy, which integrates visual, auditory, kinesthetic, and collaborative learning experiences within the same lesson. By presenting chemistry concepts through multiple representations and active learning experiences, Inclusive Teaching Strategy reduces abstraction and supports deeper conceptual understanding. Students are able to visualize chemical processes, listen to explanations, engage in hands-on activities, and learn through peer interaction, all of which contribute to improved academic performance. In contrast, while the Lecture Method provides structured explanations that may support conceptual clarity, it relies predominantly on verbal instruction and offers limited opportunities for active engagement and experiential learning.The finding of this study is consistent with Mudaly and Singh (2016), who reported significantly higher achievement among learners taught using multiple representations compared to those taught using conventional methods. Similarly, Permatasari et al. (2022) found that learners exposed to multiple representations in chemistry instruction demonstrated improved conceptual understanding and academic performance. The result also aligns with Hattie (2012), who emphasized that instructional approach that actively engage learners and make learning visible have stronger effects on academic achievement than predominantly teacher-centered methods.
The second finding of the study showed that there was no significant difference in the achievement of male and female students taught using Inclusive Teaching Strategy. Although male students recorded a slightly higher mean score than their female counterparts, the difference was minimal and not statistically significant. This suggests that Inclusive Teaching Strategy benefits both male and female students equally and is therefore not sex-biased. The absence of a significant sex difference may be attributed to the inclusive and flexible nature of the instructional strategy, which accommodates diverse learning preferences without favouring any particular group. By providing multiple pathways for understanding chemistry concepts, Inclusive Teaching Strategy creates equitable learning opportunities for all students, regardless of sex. This finding supports the position that achievement differences in chemistry are more strongly influenced by instructional methods than students’ sex.This result is in agreement with Taber (2014), who argued that students’ learning outcomes in science are largely shaped by instructional experiences rather than biological differences. It also aligns with Okebukola (2015), who emphasized that learner-centered and inclusive instructional approaches promote improved achievement across diverse learner groups. Additionally, the finding is supported by UNESCO (2020), which advocates inclusive instructional practices as a means of promoting equity and equal learning outcomes for all learners.
The last finding of the study showed that there was no significant interaction effect between teaching method and sex on students’ achievement in chemistry. Although variations were observed in mean scores across instructional methods and sex, the interaction effect was not statistically significant. This indicates that the effectiveness of Inclusive Teaching Strategy and the Lecture Method on students’ achievement did not depend on whether the students were male or female. This finding suggests that instructional method and sex operate independently in influencing students’ achievement in chemistry. The effectiveness of Inclusive Teaching Strategy in improving achievement applies equally to both male and female students, reinforcing the view that inclusive and learner-responsive instructional practices support academic success across diverse student populations. This result aligns with, Agboro-Eravwoke (2022), Agboro-Eravwoke (2022) and Hattie (2012), who found no significant interaction between effect between methods and sex on achievement. It also supports OECD (2019), which reported that instructional quality and learner engagement exert stronger influences on achievement than demographic variables such as sex. However, this finding contrast with some earlier studies that reported significant interaction effects between instructional methods and learner characteristics, suggesting that contextual and methodological differences may account for such variations.
Overall, the findings of this study demonstrate that while both Inclusive Teaching Strategy and the Lecture Method can improve students’ achievement in chemistry, Inclusive Teaching Strategy produces significantly better outcomes. Its ability to integrate multiple instructional approaches within the same lesson enhances conceptual understanding, supports active engagement, and promotes equitable learning experiences for all students. The absence of significant sex differences and interaction effects further underscores the value of Inclusive Teaching Strategy as a learner-responsive approach capable of improving chemistry achievement across diverse student groups.
6. Conclusions
In line with the findings of the study, the following conclusions were drawn:
6.1. Inclusive Teaching Strategy is more effective than the lecture method in improving secondary school students’ achievement in chemistry.
6.2. Inclusive Teaching Strategy enhances the achievement of both male and female students equally and is therefore not sex-biased.
7. Recommendations
Based on the findings of the study, the following recommendations are made:
7.1. Chemistry teachers at the secondary school level should be encouraged and trained through workshops and seminars on the effective use of Inclusive Teaching Strategy, particularly the integration of visual, auditory, kinesthetic, and collaborative approaches, to enhance students’ achievement in chemistry.
7.2. Teacher education programmes should be reviewed to include Inclusive Teaching Strategy as a core instructional approach, so that pre-service chemistry teachers acquire the necessary skills for its effective classroom implementation.
7.3. Curriculum planners and policymakers should integrate inclusive teaching components into the chemistry curriculum and schemes of work to promote instructional practices that support diverse learners and improve academic achievement.
7.4. Teacher educators should ensure that pre-service chemistry teachers apply Inclusive Teaching Strategy during teaching practice exercises to strengthen their competence in using learner-responsive instructional methods.
8. Limitation and Future Research
The study was limited to public secondary schools in Edo Central Senatorial District, which may restrict the generalization of the findings to other districts or school types. In addition, students’ achievement was measured using a multiple-choice Chemistry Achievement Test. Future studies may involve broader samples and incorporate essay or performance-based assessment instruments.
References
Adom, D., Mensah, J. A., &Agyem, J. B. (2023). Universal design for learning as an inclusive pedagogical approach: Implications for teaching and learning in diverse classrooms. Journal of Education and Practice, 14(3), 45–56.
Aina, J. K., &Sofowora, O. A. (2020). Improving the teaching and learning of science in Nigerian schools: The role of instructional strategies. Journal of Education and Practice, 11(3), 23–31.
Agboro-Eravwoke, O. U. (2022). Using ethno-chemistry approach to improve students achievement in chemistry: A case study of senior secondary school students in Delta State. Innovations; 68; 190-201
Ajaja, O. P. (2013). Which strategy best suits biology teaching? Lecturing, concept mapping, cooperative learning or learning cycle?Electronic Journal of Science Education, 17(1), 1–17.
Ajaja, O. P., &Eravwoke, O. U. (2010).Effects of cooperative learning strategy on junior secondary school students’ achievement in integrated science.Electronic Journal of Science Education, 14(1), 1–18.
Alquraini, T., &Rao, S. M. (2020). Universal Design for Learning: Implementation, challenges, and implications for inclusive education. International Journal of Educational Research, 101, 101576. https://doi.org/10.1016/j.ijer.2020.101576
Bethel-Eke, E., &Eremie, M. D. (2017).Learning styles and academic performance of secondary school students in science subjects.International Journal of Innovative Education Research, 5(4), 1–10.
CAST. (2018). Universal Design for Learning guidelines version 2.2. CAST. http://udlguidelines.cast.org
Global education monitoring report 2020: Inclusion and education – All means all. UNESCO Publishing.
Hattie, J. (2012). Visible learning for teachers: Maximizing impact on learning. Routledge
Johnson, B., & Christensen, L. (2000). Educational research: Quantitative, qualitative, and mixed approaches. Allyn& Bacon.
Mayer, R. E. (2020). Multimedia learning (3rd ed.). Cambridge University Press.
Mudaly, R., & Singh, S. (2016). Effect of multiple representations on students’ understanding of chemistry concepts.African Journal of Research in Mathematics, Science and Technology Education, 20(2), 113–124.
National Commission for Persons with Disabilities.(2024). National standard operating procedures on inclusion and access of persons with disabilities to pre-tertiary education.Federal Government of Nigeria.https://ncpwd.gov.ng
Njoku, Z. C., &Abdulhamid, I. (2016).Enhancing students’ understanding of chemistry concepts through discussion-based teaching.Journal of the Science Teachers Association of Nigeria, 51(2), 76–85.
Nunnally, J. C., & Bernstein, I. H. (1994). Psychometric theory (3rd ed.). McGraw-Hill.
OECD. (2019). PISA 2018 results (Volume I): What students know and can do. OECD Publishing.
Ojonugwa, A. A., Salihu, M. A., &Abubakar, S. (2023). Hands-on laboratory activities and students’ learning outcomes in chemistry.Journal of Science and Technology Education, 7(2), 89–102.
Okebukola, P. A. O. (2015). Teaching science in Nigeria: Issues, challenges and prospects. Heinemann Educational Books.Pp 12-15
Permatasari, D., Setiawan, A., &Nugraha, I. (2022). Multiple representations in chemistry learning: A systematic review. Journal of Chemical Education, 99(4), 1512–1524.
Rao, K., Ok, M. W., & Bryant, B. R. (2014).A review of research on Universal Design Educational models.Remedial and Special Education, 35(3), 153–166.
Rose, D. H., & Meyer, A. (2002).Teaching every student in the digital age: Universal Design for Learning.ASCD.
Taber, K. S. (2013). Revisiting the chemistry triplet: Drawing upon the nature of chemical knowledge and the psychology of learning to inform chemistry education. Chemistry Education Research and Practice, 14(2), 156–168. https://doi.org/10.1039/C3RP00012E
Taber, K. S. (2014). Student thinking and learning in science: Perspectives on the nature and development of learners’ ideas.Routledge.https://doi.org/10.4324/9780203695081
UNESCO. (2020). Global education monitoring report 2020: Inclusion and education – All means all. UNESCO Publishing.https://www.unesco.org/gem-report/en/2020-inclusion
Wiseman, D. G. (1999).Research strategies for education.Wadsworth Publishing Company.
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