Computer-based learning environments commonly comprise symbolic as well as static and dynamic pictorial representations, frequently combined with the possibility of modifying them interactively. While multiple, dynamic and interactive external representations have the potential to improve learning in various ways, they also place specific demands…

Evaluation studies conducted in 1978 at three sites yielded encouraging results regarding the ability of the Basic Skills Learning System (BSLS) to achieve the goals of adult basic education and demonstrated that effective curriculum models utilizing well-designed instructional paradigms can offer high quality instruction in the basic skills when…