When can you gauge that your kid is going to be excellent at school?

I surely think my little girl's got some powerful wit and intelligence. However, I think its different when they're in school. Both my husband and I are achievers back in school, and we're pretty excited to hear the same for our kids. If being academically excellent runs in the genes, I can relax now, but if entails more than that, I sure hope its something easy to cover. She is in Kindergarten now, and her workbooks show good scores - almost all are perfect scores. But of course, their topics are really easy, like shapes and colors, etc. Im just wondering if getting good scores at school, as young as 3 or 4 years old, is already an indication of academic excellence.