Our BIG question is, how/when can our son get in-state tuition in Texas if we only just move there the summer after his high school graduation?
Your son will not be considered a Texas resident for tuition purposes until you have resided in Texas for 12 consecutive months. And, even then, if he has already enrolled at a Texas public college or university as a non-resident, he will not automatically be granted in-state status at the end of the first year. He will have to apply for it, and the determination is made on a case-by-case basis by the individual schools. If your intent to remain in Texas is clear (more on that in a minute), then your son’s reclassification is probably just a formality, but you still need to understand that it is not a sure-thing.
Once you relocate to Texas, you shouldn’t plan to move into your sister’s rumpus room and drive around on your Ohio licenses if you want the 12-month clock to start ticking right away. This website from the University of Texas provides a helpful list of things that you need to do to establish your Texas residency, and your year won’t begin without documentation that you have officially launched this process. Note, however, that residency requirements can vary at least a little bit from one public college to the next. So once your son has his eye on some options, you should research the requirements at these schools individually.
If you are fairly certain that your son will attend a public college in Texas, you might want to encourage him to take a “gap year” after he graduates from his high school in Ohio. That way, you wouldn’t get stuck paying a year of out-of-state tuition in TX, and your son wouldn’t have to petition for reclassification after starting college. Since many students opt to take a gap year anyway, even without this big incentive, this could be a wise strategy for him and … especially… for the parents who will be picking up the tab for his higher education!