My first rule of thumb is to donate anonymously. If you want to help and are worried about perception this is 100% the way to go. This is certainly an option when giving to college programs. If that is not possible I would stress money comes with no strings attached and you need to mean that (and you really need to mean that).
High school donations where I live are mostly related to buying a car wash or a water bottle etc. They don't come looking for big money. Believe it or not, in all the years of travel I don't recall opportunities or needs to donate to travel.