Personally, I don't think it is appropriate for schools to use the money raised by donations to pay tuition fees.

First of all, when the school initiated the fundraising, it did not explain what the money was for. This is wrong.

Then the school uses a special "gift-returning" behavior to let itself collect tuition fees, which is morally inappropriate.

Finally, I personally think that the strategy of killing two birds with one stone in the school is really high.

As for the school foundation you mentioned, it is allowed. Many schools have such foundations to help students with difficulties.