I've had thoughts about this subject for quite a while. I could see a scenario where a college is held to the verbal for one year (of the scholarship offer, not a playing position). A verbal contract can be valid under the right circumstances. The problem for the student is that there must be consideration given on each side for a contract to be valid. In other words, each side must be giving up at least something. Because I do not think a 15-17 year-old student is going to be held to a verbal by a court, I'm not sure what she is actually giving up in issuing her verbal. She could argue that, in her mind, she gave the verbal with the intention of no longer considering other schools. If she in fact follows through on that intention by ending the marketing process, I could see a decent case.
Because scholarships are only good for one year, that is likely all that a plaintiff would be awarded. And if the new coach doesn't want the player, is it really worth it to sue and get your one year, knowing you're not wanted there?
The legal reasoning behind my theory is that it is the school making the verbal to the player, not the coach. The coach literally makes the verbal promise, but the coach works for the school and does it on behalf of the school. It is the school's money that the coach is spending and the school that the coach is representing. By knowingly permitting coaches to make verbals, colleges are ratifying their validity, and thus, standing behind them. Because the college is in such a superior position over a student in the process, courts will tend to favor the student in these situations. The colleges would be thought to be in a superior position for several reasons: Coaches regularly engage in this negotiating and students and their parents usually only go through it once; coaches are adults and students are kids; coaches are expected to understand recruiting rules to the letter, whereby families understandably will struggle; the recruiting process is mostly business for coaches, but is also emotional for families.
Finally, I can see a judge simply saying to himself, "If you guys are going to make promises to 15-year olds, I'm going to hold you to them, you a$$holes." That might be a judge's first thought and then he'll work backward from there to get that result.