The purpose of this study is to indentify the relative effects of general and specific formative evaluation on the academic achivement of the low academic students. The general formative evaluation is defined as the usual formative evalution which is used in the class, and the specific formative evaluation is defined as the evaluation which includes two kind of function such as instruction and formative evaluation. Therefore, this study hypothesizes that the specific formative evaluation can help learning for the lower academic students. The subjects are 187 6th graders of a primary school in Taegu. They are divided into the high(50), the middle(87), and the low group(50) in terms of the readiness test scores. The high and the middle academic achievement group students are administered the general formative evaluation. The low academic achievement students are again divided into two groups. And one group is administerd the general formative evaluation and the other is administered the specific formative evalution. The learning task is a arithmetic unit of decimal fraction in the text. They were taught for 7 academic hours and administerd 7 formative evaluations. They were administered immediate test and delayed test two weeks later after treatment. Two-way ANOVA and Scheffe Post-hoc test were used to compare the relative effect of generl and specific formative evaluation on academic achivement for the lower achivers. The results of this study are as follows First, The students who were administered formative evaluation including made higher scores than the control group students including all of 3 ability groups. Second, the students who were administered the specific formative evaluation made higher scores than the students who were administered the general formative evaluation in case of the low achivement groups.