Tell him to 'lax the crack. Whut, whut?
On a serious note, ask him if he's tried little songs or jingles. They can really help, depending on the subject matter. For math and science, I recommend trying to imagine a graph, diagram, or visualizing something- anything; learn to associate pictures with certain words. If he has got a serious problem though, tell him to get serious help. These things don't just go away in time.