in my opinion that  this article mention instructionism and constructivism. instructionism is teacher-centered aproach. constructivism is student-centered aproach. at the first stage used instructionism in education . but the world rapidly changed about  economy,industry and tecnology. for these reasons constructivist approach being used
in education.constructivist approach, which is an important collaboration, problem solving, thinking, etc. at the forefront of things.in addition, in this article mention effect of computer assited instruction at past. and today it says that  we use better than past .
my questions:1) how is the prior knowledge about effect of learning?
                        2) how much can we benefit from CAI at science and how many percent of experiment at science?