20dad is correct, if the money goes to the school from the fund no taxes, if to you, taxes but I do beleive that amount is reported to the IRS. Not sure of that.
He is also right in stating that unless they really want to sign you, don't expect 4 years at the school of your choice, regardless of where the player is heading, but then again that is something that is negotiable. Not sure if inflation is covered, but remember they want to give you as little as they can.
My player was given more than he needed to finish 32 credits, but with inflation, the loss under the bonus incentive plan he has had to put money aside so that he can cover tuition without loans. The money given did not cover living expenses. You better assume that your player will have to work and attend college after he leaves pro ball unless you can support him later on. If he is lucky to get some time in on the MLB level, that will help.
If you are a former player, some schools have funds available to help, but there are stipulations as to time frames, they do want you to graduate and will do whatever they can to help.
All teams do things differently, one team wanting to draft son out of HS would only give in state tuition, not what his scholarship was worth in South Carolina.
If this is something you need to seriously consider if the player is going to sign out of HS, go to college first and get some time in the classroom, tehy will pay you going back to that school to finish, even at expensive private schools. JMO.