I don't find this at all surprising:

"There have been no advances over the past decade that can be confidently attributed to broader access to computers," said Stanford University professor of education Larry Cuban in 2001, summarizing the existing research on educational computing. "The link between test-score improvements and computer availability and use is even more contested." Part of the problem, Cuban pointed out, is that many computers simply go unused in the classroom. But more recent research, including a University of Munich study of 174,000 students in thirty-one countries, indicates that students who frequently use computers perform worse academically than those who use them rarely or not at all.

Output requires not only inputs but their employment in proper combinations. That requires entrepreneurs interested in maximizing economic efficiency. Computers in a classroom require teachers skilled in their use for education; computers used at home are often used for playing games or chatting. Making a child work in front of Encarta or Britannica Online are passe; Littlest Scholar does her "computer schoolwork" using Google. I see no reason to believe that is somehow going to enhance her performance in the classroom.

My teacher-readers -- please comment on this. LS's school is in need of computers, but when I asked why, the request was for replacing worn-out CD drives. Now that struck me as interesting; the Internet isn't the issue. What kinds of software are used? I wonder if the tests discussed in the quote were done separately for those for whom computer use=Internet search and those for whom computer use=teaching software, we might get a different result. But I really don't know.