Helen Quinn ( Physics Today, January 2007, page 8) makes a very good point that the general public often misunderstands the meaning of “belief” and “theory” as used by scientists. The problem originates, I believe, in the way science is taught in the schools. As Thomas Kuhn noted long ago in The Structure of Scientific Revolutions (University of Chicago Press, 1962), science is taught like religion: You’d better believe it or you will get a bad grade. Fundamentalists opposed to evolution have a stronger threat: You’d better not believe it or you will go to Hell.
Today, as a result of the No Child Left Behind Act, US public schools place increased emphasis on testing. Unfortunately this motivates teaching to the test, with little emphasis on the scientific method.
The most important thing to be taught is how scientists have come to believe the present theories, usually after a long struggle, as a result of many experiments and observations. Even for a limited part of physics, it is hard for a student to recapitulate in a semester what may have taken scientists many years to discover. There is always an attempt to cover too much material, as evidenced by the weight of the latest university physics textbooks, which only the stronger students can lift. There is no simple solution, but it is important to identify the problem.