|dc.description.abstract||English as a language of instruction is recommended in the Nigerian mathematics classroom, it is also a second language where both teachers and students necessarily use at home to communicate. The study aimed at establishing the effect of English as a second language in teaching and learning of mathematical modellling at junior secondary school level in Nigeria. The junior secondary two learners in Nigeria are second language students who learn mathematics and particularly word problems inmultilingual classrooms. Specifically, the research was to; establish teachers‘ proficiency level of English as a medium of instruction in mathematics classroom, establish teachers‘ preparedness as they teach word problems in English, determine the effect of English Language on teaching and learning of mathematical modelling (word problems) with regard to students‘ performance, determine the effect of mathematical modelling on gender performance and developed mathematical modelling approach for mathematics junior secondary school teachers in Nigeria. The Solomon Four Group design was used as a research design for the study. The design used data obtained from both the pre-test and post-test in the four groups. The instruments used for data collection in this studywere interviews, Mathematics Teacher Questionnaires (MTQ), Students‘ Achievements Test (MWPST) and the classroom observations. The total sampled of the population used in the was 430 (number of teachers 10 and number of students 410). The study used non-proportional and purposeful sampling techniques in chosen the sample.Data from the research instruments were coded and analyzed using Statistical Package for Social Sciences (SPSS) version 17. Analysis of Variance (ANOVA) and independent t-test were used to test hypotheses at 0.05 level of significance. Analysis of data generated from studentspre-test revealed that, the effect of English on students‘ performance in word problems was insignificant (t (203) =0.919, p>0.05). This revealed that students‘ performance was the same before the commencement of the treatment. Post-test result from the study on the effect of English language on students‘ performance indicated a significant difference (F(402)=48.63, p=0.01, p<0.05).This implies that interventionalstrategy (Mathematical Modelling) has significantly improved the performance and problem solving abilities of those groups who were given treatment (experimental)‗ in word problems more than those who were not given the treatment (control). Results of the post-test mean scorebetween the treatment (experimental groups) and controlled groups show a significant difference (p < .05). The data also suggest that the interventional strategy (mathematical modelling) in the posttest positively influenced gender performance and shows a significance difference (t (108) =13.16, p >0.05) in word problem-solving abilities. This implies that gender performance in the post-test was not similar but an increased their performance.Overall results in this study illustrate that number skills displayed bylearners seem to be directly related to language use in the classroom.
Key words; Language, Second language, English language Proficiency, Modelling, Mathematical problem solving. Real word problems, students.||en_US