Evidence collected on the effectiveness of four educational technologies is briefly reviewed. The authors conclude that there is reasonable evidence that computer-assisted instruction can have at least a modest effect on improving learning and probably more when its instructional approaches are properly matched to instructional objectives, that the findings supporting use of computer games for instruction are thin but promising, that evidence supporting use of computer tutors is equally thin but equally promising, and that, even though Advanced Distributed Learning has been widely accepted by the training community, it is not commonly used in education and research remains needed to determine its impact and effectiveness.