small and not serious confessions please

This brings back a bad memory from when I asked the community something similar and someone's answer was horrific. I'll spare the details and answer normally below.

I went to a catholic school (they are state funded and popular where I grew up). We were offered to do something called confession a few times a year which usually took up 30 minutes of class.
I would leave to confession and just go hang out with friends.
I got caught once by a teacher. I told the teacher I will add it to my list for the next confession.