The purpose of this study is to examine the effects of the implementation of formative assessment on student achievement in elementary algebra classes at Richard J. Daley College in Chicago, IL. The formative assessment is defined in this case as frequent, cumulative, time-restricted, multiple-choice quizzes with immediate constructive feedback. The impact of this endeavor is measured by summative external (the national standardized COMPASS Test) and internal (departmentally designed) assessment instruments. The research is guided by three primary hypotheses. First, the use of formative assessment could reveal the levels of conceptual understanding in a timely manner allowing for continuous readjustment of teaching and learning strategies, thus improving student academic achievement. Second, an increase in frequency of formative assessment will provide better results on summative assessment. Third, the results achieved on valid and reliable internal summative assessments are an accurate predictor of the external examination scores. Using a four-group experimental and correlational design and t-test for significance analysis, it was found that after approximately four months the students (N=222) who were regularly assessed with weekly quizzes achieved significantly higher scores on the final examinations than the students (N=1352) whose instruction did not include formative assessment at all. The higher outcomes attained were in conjunction with higher retention rates. An increased frequency of formative assessment did not produce a significant improvement in students' learning outcomes. The results obtained on internal summative assessments were also highly correlated to the external examination scores. (Contains 5 figures and 11 tables.)