It also could mean she got lucky on one test. I"ve read many posts on this site about kids scores dropping when they get older and it's always the teachers fault. Maybe it's just the way things work out. I know this is a simplistic example but when I was in kindergarden I was the tallest kid. I was going to be a basketball player. I ended up 5 ft. 8 in. More my point is some kids just peak earlier than others.
About the one test: possible. Obviously we have limited information. That's just my take on what little is there.
I'm not sure the height analogy fits, though, unless your parents started withholding food. Because it's a common experience for gifted kids that they grow up in a heavily enriched environment, and then find themselves in elementary school, where their needs are all but ignored. If you don't use it, you lose it.
Now, if you were bench-pressing your own body weight as a kindergartener, and the school suddenly switched out your metal weights for foam, that might be a better analogy.
