This research aims to find out about the effect of corrective feedback to homework on the ability of solving problems of thermodynamics in class X of SMA PGRI 1 Pontianak. This research was a quasi-experimental design with a nonequivalent control group design. The sampling technique used the intact group. The samples were 28 students in the experimental class and 30 in control class. The results show that the average score of students with corrective feedback is 37.11 and without corrective feedback was 31.87. The average percentage of students\u27 ability in the problem solving stages with corrective feedback was 71.43% and without corrective feedback was 60,83%. The results of calculations using polled variance t-test show that there are differences in the ability of solving problems of thermodynamics between the two classes with t-count > t-table (2.08 > 2.00). Corrective feedback had a positive effect with ES = 0.64 and categorized as moderate and gave a contibution of 23.89%. Based on the research, corrective feedback should be given to materials, types of test and different problem
