Are my 2 friends going to get expelled?

My 2 friends are pot heads. I have never liked it, but we have known eachother forever so we have always been best friends regardless. We are in the 10th grade, almost every morning, they would go by a creek that is on school property, and bring a bong with a lot of weed, they would smoke it all and go through the school day high as a kite. On friday, this time, someone was watching the cameras, and they saw those 2 walking over by the creek 30 minutes before any kids were even at the school. So the princable started walking down. By the time he opened the door, he could smell it. He started to follow the smell, he walked all the way over and caught both of them. One of them tried to ditch what weed he had left, along with a pipe. They were pulled into his office. He ordered locker and person searches. In both of their backpacks were about 7 pipes, lighters, and some left over weed. They were both suspended for 15 days. Everyones saying it might go to the school board and become an expulsion. Please help me tell me what will happen!! They both have been suspended a lot for different reasons this year.