Statistics on computers in schools fly fast and furious. Nearly all of the public schools in the United States are now hooked up to the Internet, but the location of computers in the school and how often students have access to them may make all the difference.

"These statistics mask a lot of diversities," said Robbie McClintock, the director of the Institute for Learning Technologies at Teachers College, Columbia University. He gave two examples of how 100 computers could be allocated among 100 students: in four computer labs with 25 students each, or in five classrooms, where each of the 20 students would have a computer. "These distributions lead to a very different educational experience even though the ratio is the same," Professor McClintock said.

Students scheduled to work in computer labs for an hour each week often do drill-and-practice lessons in subjects like typing or math, he explained. Those in a classroom setting can use the computers anytime. In one 16-week program, for example, students use software to learn about the ancient world by excavating a virtual site in ancient Mesopotamia or Greece.

The best educational model, Professor McClintock said, is one in which a student can take a laptop home every night. "This moves the education program from the school into the students' hands on a 24-hour basis," he said.

When asked to compare the growth of computers in schools to previous advancements in education, Professor McClintock reached all the way back to the 16th century and the introduction of printed books into Western culture. "This is a long-term process of fundamental educational change," he said. "Schools need to have plans for 10 or 20 years out to integrate the technology tools into their programs."

Ultimately, the value of technology in education is up to the teachers. "The experience can be very good," he said, "or it can be like wheeling a VCR into a classroom and turning it on."