Well I'm going into the 8th grade and in 7th grade I was really bad like got into fights yelled at teachers but sense I'm going into the 8th should I act better

I think you should always seek to improve upon your past behaviour. What "improve" means, is up to you.

Well know that firstly you can't win in a fight against a teacher. I'm 15 and in High school and I see kids trying to be "all that" to a teacher and they just look like idiots. Can you give us more detail on why and how you got into fights or yelled at teachers.

Well im goin into the 8th grade and in 7th grade i was really bad like got into fights yelled at teachers but sence im goin into the 8th should i act better
Yes, That how u get respect. Acually the teachers will give into you more. I was in 9th grade got arrested 13 times in a school year for skipping and fighting the trouble is not worth it trust me.

Of course you should act better. You also may want to consider counseling to get to the root causes that motivate your current behavior.

Check to see if your prison population is full or not, We need to keep all of our prison guards and workers fully employed, so we need enough people like you not to change, to keep them all in work.