baseballmomx4, keewart has shared the basic NCAA rule with you, which is a great starting point. In addition, some Division I conferences may have a requirement that is a bit more strict than the NCAA. (So, for example, 2.00, regardless of the examples of 1.8 or 1.9 as in what keewart pulled from the NCAA site.)
I often tell parents that Division I athletes should think of 2.600 as the GPA minimum. This article from our website explains why: