Abstract:
The purposes of this research were: 1. to study the effects of using open-ended problems on mathematics learning achievements of lower secondary school students. 2. to compare the mathematics learning achievements of lower secondary school students between groups with high, medium, and low levels of mathematics learning after using open-ended problems. 3. to compare the mathematical creativities of lower secondary school students with high, medium, and low levels of mathematics learning before and after using open-ended problems. 4. to compare the mathematical creativities of lower secondary school students between groups with high, medium, and low levels of mathematics learning after using open-ended problems. The subjects were 110 mathayom suksa one students in academic year 2004 in Sriyapai School, Chumphol province. The experimental instrument was the lesson plans using open-ended problems and the research instruments were the mathematics learning achievement test and the mathematical creativity test. The data were analyzed by means of arithmetic mean, standard deviation, t-test, One-Way Anova and Scheffe' Method. The research results revealed that: 1. Mathayom suksa one students being taught by using open-ended problems had mathematics learning achievement of 58% which met minimum criteria of 50%. 2. After using open-ended problem, students with high level of mathematics learning had higher mathematics learning achievement than those with medium and low levels of mathematics learning, and students with medium level of mathematics learning had higher mathematics learning achievement than those with low level of mathematics learning at .05 level of signigicance. 3. After using open-ended problems, the mathematical creativities of students with high, medium and low levels of mathematics learning were higher than those before using open-ended problems at .05 level of signigicance. 4. Students with high level of mathematics learning had higher mathematical creativities than those of students with medium and low levels of mathematics learning at .05 level of signigicance but there was no significant difference of mathematical creativities between students with medium and low levels of mathematics learning