This research was aimed at: 1) assessing mathematical problem solving
ability of students following problem-based learning; 2) assessing mathematical
problem solving ability of the students following guided discovery learning; 3)
assessing if mathematical problem solving ability of the students following
problem-based learning is better than the ability of the guided discovery learning
students. The population was all students of VII grade of SMP Negeri 1 Baturaden
and the sample was determined by cluster random sampling technique. The
students of class VII C was the experimental class, class VII A was the control
class, and class VII B was the post test try out class. Based on the descriptive
analysis of the data, the mean of mathematical problem solving ability in
experimental class was 38.647 with 18 (52.94%) students scored higher than the
mean. The mean of mathematical problem solving ability in control class was
33.412 with 15 (44.12%) students scored higher than the mean. The data were
analyzed through SPSS 16.0 program and the conclusion was drawn based on the
significant value. After right-tailed T-test was applied, it was obtained Sig. (one
tailed) = 0.022 with α = 0.05. Since Sig. < α, H0 was rejected and Ha was
accepted. It could be concluded that mathematical problem solving ability of the
students following problem-based learning is better than the ability of the guided
discovery learning students.