So. Is it possible to practice for an IQ test? No idea. But if it is, I'm sure there are parents in your district doing so as we speak.
That is, of course, all from older versions of these tests prior to the mass level of studying going on now a days.
I'm sure that there are ways to study for IQ tests, but I can't imagine that it is wise to do so. The goal of such a test is not to get an artificially inflated number so you can misplace the child in a program for which s/he isn't truly qualified. The problem when that becomes widespread is that these program are no longer filled with kids who are needing that level of programming and the programming adjusts to who it is actually serving not who it purports to serve.