If your daughter is in school she has probably taken plenty of tests so she is aware of the concept. Are you taking it through a talent search? If so, They probably got her name from...tests, right? State tests? The only prep you really need to do is to get a practice test, either from the talent search or the library, and have her do it at the kitchen table. DS practiced it in two chunks, on two Saturday mornings, so the first time he took the whole thing was on the test day when he was 11. The practice was mainly to get a feel for how long it is, and how many ovals you're going to be circling, and when to use the calculator. We didn't do any more prep than that, because it was a way to see where he was truly at.
That's about the same general level of "prep" that my DD13 used when she took the ACT for real as a junior in high school, btw.
ITA-- this isn't the kind of high-stakes testing that would make one consider intensive prepping as you truly just want the information and don't intend to share the scores other than for gaining appropriate opportunities in the next few years. It's not college admission on the line.
