The 1981 Basic Skills Summer School Program in Montgomery County, Maryland public schools provided intensive remedial instruction in reading, writing, and mathematics to pupils who scored very low on national standardized achievement tests. An evaluation of the program's effects found that (1) over all, participating students in grades 4-8 scored significantly higher than nonparticipants in mathematics (especially in grades 7 and 8), but there was no discernible difference in their reading or vocabulary scores; (2) at the end of the first semester, the grades of participants were higher in all areas than those of nonparticipants; and (3) school attendance of former participants was much higher than that of nonparticipants. (Author/WAM)