A study by a Nobel Prize-winning physicist — now a science adviser to President Barack Obama — suggests that how you teach is more important than who does the teaching. He found that in nearly identical classes, Canadian college students learned more from teaching assistants using interactive tools than from a veteran professor giving a traditional lecture. The students who had to engage interactively using the TV remote-like devices scored about twice as high on a test compared with those who heard the normal lecture, according to a study published Thursday in the journal Science.