The HBPL is a league which stands for Handicapped bar pooping league. What you do is stand on the handicapped bars in a toilet stall over top of the toilet. You then pinch one out and attempt to make it in the toilet bowl. If you miss you lose. Double points are awarded if you manage to hit the seat and still make it into the water leaving a poop smear on the seat.
Did you see Joe win the HBPL tournament at school the other day. He went 10 for 10!!!