HECK NO ITS NOT RIGHT!!!! Let them do anything they want to. We all know that training rules are "old school" and really don't mean anything. We all know that school sports really have nothing to do with schools anymore and that it is no longer special to represent your school and community; no sacrifice is necessary--ESPECIALLY if it means giving up something YOU like to do! or, <GASP>, committing yourself to something bigger than yourself.
Sorry for the rant. Just get so tired of people agreeing to rules and then being appalled and outraged when they are actually enforced -- on them.
If the kid and parent signed the agreement then why is this even an issue? Extracurricular athletics are NOT a required part of the student's education.