Özet:
This study aimed to develop and measure the effectiveness of an instruction enriched with combination of contextual problems and student centered teaching episodes with regard to the extent of change in students' achievement in trigonometry, and their views and perceptions about trigonometry. In order to analyze the effectiveness of the developed instruction on trigonometry achievement, and views and perceptions about trigonometry; a true experimental design was implemented in an Anatolian High School in Istanbul with the participation of 74 (Grade 10) students. 24 students received traditional instruction (Group A), 26 students received an instruction enriched with only contextual problems (Group B) and 24 students received an instruction enriched with combination of contextual problems and student centered teaching episodes (Group C). Data obtained (through Trigonometry Achievement Pretest, Trigonometry Achievement Posttest, Views and Perceptions about Trigonometry Prequestionnaire, Views and Perceptions about Trigonometry Postquestionnaire and interviews) from the sample were analyzed to examine the effect of instruction enriched with combination of contextual problems and student centered teaching episodes. IGuscal Wallis Test was used in order to examine whether there is a significant difference between groups' trigonometry achievement after instructional sequences. The results of the analysis indicated that the group who received instruction enriched with combination of contextual problems and student centered teaching episodes (Group C) performed significantly higher than the group who received traditional instruction (Group A), the group who received instruction enriched with contextual problems (Group B) performed significantly higher than the group who received traditional instruction (Group A), but there was no statistically significant difference between the group who received instruction enriched with combination of contextual problems and student centered teaching episodes (Group C) and the group who received instruction enriched with only contextual problems (Group B) in terms of trigonometry achievement of students. As a result, a positive effect of the instruction enriched with contextual problems on students' trigonometry achievement was found compared to traditional instruction. However, results implied that instruction enriched with combination of contextual problems and additional student centered teaching episodes may not have a significant positive effect in improving trigonometry achievement compared to the instruction enriched with only contextual problems. Long term effects of instructional sequences on trigonometry achievement among groups were also explored in the study. The nonparametric test of Kruscall Wallis was used for the analysis of data and results indicated that there is significant difference in terms of retention test scores between Group A and Group B, and Group A and Group C. However, there is no significant difference between Group B and Group C in terms of retention test results. This result was parallel with the results of the immediate effects of instructional sequences on trigonometry achievement. As a further analysis, Related Samples Wilcoxon Signed Ranks Test was also carried out to compare retention test scores and posttest scores for each group. The results indicated that there is permanance of the trigonometry achievement for Group A and Group B, however there is no pelmanance of the trigonometry achievement in Group C. Views and perceptions about trigonometry after instructions were also explored for each group. Descriptive analysis done on five questions asked before interventions and six questions asked after interventions implied that instruction enriched with combination of contextual problems and student centered teaching episodes has positive effects on students' views and perceptions about trigonometry compared to the traditional instruction and instruction enriched with only contextual problems. The results also provided evidence on what students perceived to be most interesting and meaningful about the instructions.