Above level tests, such as the SAT, taken as a 12 year old, are one way to document LOG. The talent search groups will provide a bell curve for the kids, all in the top 5%, so gifted by many definitions, of the same age who took the SAT through them. Of course, I haven't really heard of any kids who took the SAT before age 9, so this info may not help right now.

HTH
Grinty

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