Snowball throwing based on lesson study to improve college student's algebraic reasoning in solving problems generating functions

This study aims to describe the improvement of students' algebraic reasoning in solving generating function problems based on implementing lesson study-based snowball throwing learning model. The subjects this were students odd semester STKIP PGRI Sumenep mathematics education program who had passed courses mathematical logic and number theory. research is a type classroom action with qualitative approach. Lesson CAR have many similarities terms stages, namely planning (plan), implementation & observation (do), reflection (see). instruments problem-solving task sheets sheets. Data analyzed using quantitative descriptive analysis by describing percentage data obtained. On indicator looking for patterns, there was an increase 50%, finding patterns 43.75%, while generalization 45%. shows that model can improve problems.