In this study we examined the relationship between the attitude of children with poor working memory and the characteristics of teachers' revoicing in mathematics classroom discussion. Three children with poor working memory and three children with average working memory were selected from each of two fourth-year classes by computer-based working memory assessment, and observed in mathematics classes by two teachers using different discussion-centered approaches. The classes were also videotaped and teachers' and childrens' utterances were transcribed. The following were the main results: In classes with one teacher (T1), the children with poor working memory listened carefully to the teacher's explanation and classmates' opinions at the same rates as the children with average working memory did, whereas in classes by the other teacher (T2), the children with poor working memory did not listen to the teacher's explanation and classmates' opinions as carefully as the children with average working memory did. When teachers' utterances were analyzed, T1 used more revoicing than T2 did. It is suggested that the teacher's revoicing helped children with poor working memory understand and follow the discussion in mathematics class.