1. You have to ensure that the board of trustees have approved this sale by a resolution passed by the majority members and have authorised the seller to sell the same on behalf of the trust, if it is not available then the sale cannot be held as a legally valid sale.
2. The school comes under trust hence even if she is becoming a member of the trust, until the trust is passing a resolution to sell this proeprty, she cannot become a owner of the school.
3. The school is already under the governance of a trust, hence you cannot shift the same to your own trust.
4. No. For anything concerned with this property,she cannot do anything except the trust has to follow the procedures as mentioned above.