How do I get back at my fave teacher :3?

Me and my wood shop teacher (my favorite class) have this practical joke think going on. It all started when he locked me in a display case at the end of last year. Since then we have gone back and forth pranking each other. Like, I duck taped him to his chair, he glued me to my deck chair. I put perfume in his hat ( he hates perfume), he hid my Co2 car. His latest stunt was when he dumped a bucket of wood and acrylic shavings on my head and it took me the rest of the day to get it out. Now I'm out of ways to get back at him. What is a new way to pull a prank on him? He is very let loose, messes with all of his students, never changes grades, and I NEED REVENGE! :)How do I get back at my fave teacher :3?
Find an online shop that sells ';Fart Spray';



Spray his classroom. And him if you can. ( I would'nt recommend admitting to this prank though. For obvious reasons)



Spray the rest of the school while you're at it.How do I get back at my fave teacher :3?
Paint grenade in his car. You can get one or a box at any paintball store on or off line.

It's totally washable since its for paintball.