This is a really good question. The most recent case I could find here is the one Rayiner cited, Saenz v. Roe. If you read it, both the opinion and the dissent grapple explicitly with college tuition.
The reasoning goes, it seems, that only bona fide citizens of (say) California will consume welfare in California (you don't move to California to consume California welfare benefits in Ohio). But college education benefits are "portable"; you could conceivably move to California solely for the purpose of accumulating the benefits of a UC education, then take it back with you to Ohio.
Further, the way in-state tuition benefits are structured, the residency requirement is (supposedly) carefully tailored to address just that scenario, by imposing relatively short durational requirements on residency, rather than evidence of permanent residency.
It's tricky to piece out how health care would fit into this rubric. Depending on the condition, you might move to California to benefit from their health care and return to Ohio when you're cured, or you might need to stay in California indefinitely to treat a manageable illness.
