itch.io

If you go to the college's office on the first floor there's an explanation there, but in short:

1. Raise Education by teaching classes (do not do naughty things!)

2. Buff your education gain/loss numbers by talking to various people and buying a certain item from the Mysterious Merchant.

3. Once your Education reaches a certain point, go to the college office and call a meeting

4. Profit! Well, no, but you can change the uniforms and do "private tuition" and stuff!