Credit to Dae-chan for the idea
Harry: He taught you how to play quidditch
Ron: You learned how to bake from Mrs. Weasley
Draco: He taught you a lot more about proper manners
Fred: You learned how to pull the best pranks on people
George: You learned about DADA from Harry together
Oliver: He taught you how to plan good plays in sports
Seamus: He taught you how to blow up your potions. But in all seriousness you learned more about potions together
Dean: He showed you how to play British football (soccer for us Americans)
Neville: You know so much more about herbology now
