Why Gryffindors shouldn't take Divination

Godric Gryffindor doesn't listen, so when the other founders try to tell him not to tap the crystal ball with his wand, but are too late, they are transported to the year 1993. They meet Harry Potter and his friends, and take a certain liking to the Weasley Twins. What could go wrong? Rated T for mild language. Chapter three's author's note has been replaced with an actual chapter!