This research airned to analyze the effect of CORE learning model on the students‟s
mathematis problem-solving skills and learning motivation. This research applied the
experimental method with a posttest only control design. The population was all
grade VIII students of SMP Negeri 3 Sumbang in the academic year of 2018/2019.
The cluster random sampling technique was used to collect the sample. It was gained
two classes of sample, namely, class VIII A as the experiment class which used the
CORE learning model and class VIII B as the control class which used a
conventional learning method. The instruments used in the research were a posttest
of mathematic problem-solving skills and questionnaires of students learning
motivation. According to the result of the hypothesis test using independent sample ttes
with Level of significant was 95%, it proved that the CORE learning model
positively affected students mathematic problem-solving skills and learning
motivation.