Do you have any idea what test(s) they are giving him? Not so you can prep (I wouldn't recommend that) but b/c it is good to know if it is an IQ test, a group ability test, or what. Do be aware that, if they use a group ability test, it may or may not be the best test depending on your child. Some (like Raven's progressive matrices) only look at one area of intelligence. If that happens to be your child's strength, he may do well. If not, it doesn't mean that he wouldn't do well on another test that hits on a different area of intelligence. Some rely on a child who processes quickly b/c they are timed.

All in all, there are a lot of factors that will make a difference in his scores. If they don't qualify for the GT program, I wouldn't necessarily assume that he isn't gifted if other indicators are there.