We have not used ALEKS, so I can't post from personal experience on that. I am wondering, though, what specifically about that program leaves you worried that it will impair him in terms of SAT/ACT test scores? It doesn't matter how he solves the problems on those tests, only that he gets the correct answers. So, if ALEKS teaches an unusual method of solving problems, that shouldn't be a problem for those tests as long as your ds knows how to get to the right answer in an expedient manner.

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