teenage boys

ok so I happen to be a single mom of a 6 year old girl and a 15 year old boy. Both of whom are great kids! But my son, just doens't want to go to school! It makes me crazy! He misses the bus almost every day on purpose, skips school when I drive him! It's a total mess! I have asked him if thre is something going on at school making him not want to go? He just seems to have zero drive. He thinks he will just graduate, find a job and be ok. I know at 15 it's hard to explain why school really is important but sheesh! ugh ok enough ranting for now!