He remembers it very clearly.

A dialect opened between his parents and the Headmaster. What it came down to was a matter of safety. Not just for the safety of his peers — but for Remus. The reasons that should’ve made him stay outweighed the reasons why he should attend. His mother argued for the safety of their only son. What it would mean if anyone were to find out. His father reasoned that certain measures would be made in order to ensure that it didn't happen.

Outwardly, Remus remained impartial.

But Albus Dumbledore encouraged it, and Remus Lupin was enrolled.