This report summarizes the results of studies of four computer-assisted integrated learning systems (ILS) designed to teach students arithmetic: two in Israel (TOAM--distributed in the United States as DEGEM and SEMEL) and two in the United States (CCC and WICAT). The qualitative and quantitative studies identified cognitive, sociological, and affective effects, as well as several instructional design issues found to affect students' benefits from ILS. The report includes discussions of the following: (1) effects of ILS arithmetic practice, including aptitude-related differential effects, age aptitude-related differential effects, socioeconomic status effects, and gender effects; (2) students' attitudes towards working with an ILS, including attitudes toward ILS practice, comparisons of attitudes towards class and ILS arithmetic, and reasons for students' attitudes towards ILS practice; (3) instructional design and human-engineering issues of ILS, including encouraging cooperation or competition, applying time limitations for entering answers, ILS hardware and software issues, and the use of paper and pencil work while online; (4) students' ILS-related behavior; (5) teachers' ILS-related behavior, including the teachers' use of the class report, attitudes towards the class report, effects on teachers of ILS work and the class reports, competition-related behavior, and perceptions of ILS work on student learning; and (6) decision making through the computerized management of students' ILS practice. It is concluded that the ILSs available in schools are not yet mature in that none of the currently available ILS systems is satisfactory in all three of the following areas: a good curriculum, a good computerized management system, and ease of integration with regular school curriculum. (20 references) (DB)