Teacher not supervising kids?

I just started a job in the computer lab at an elementary school. I've been having problems with one of the sixth grade teachers. He has sent students to the lab by themselves, without a note or anything. I don't think he knows my work schedule, he has no way of knowing if I'm even there and he doesn't check. I know for a fact that the students have been in the lab unsupervised, more than once.

Today, he brought his whole class here, then after a few minutes informed me that he was leaving. He said to send students back if they were misbehaving. I ended up calling him to come back to the lab, because 90% of the class wasn't on task. I'm pretty sure he was annoyed, but whatever.

I basically feel taken advantage of. My job is to support teachers and students in the lab, not to babysit. I'm also pretty sure that some of this behavior is illegal. How should I handle this? Is there something I can do to make my point with him directly? Or should I go to the principal?

I forgot to mention - he didn't reprimand the class at all when I asked him to come back.

Well I would say go to the principal. I work in a school and that works almost all the time, the principal will take care of it and make sure he is doing his job and not you.

Try to talk with him - explain that he is the only one treating you this way and that you are going to give him the chance to address it, but that if it continues, that you will have to report him.

If I were you I would ASK the Principal for the procedure used to send children to the lab. Ask for the regulations, THEN if the teacher is in conflict, bring it to the attention of supervision.

I am under the impression that if you work in the computer lab, it IS part of your job to supervise any children that are sent to your lab while you are on duty, so you can not complain about doing what is expected. If this was not explained to you when you got the job, consult your supervisor. As for him disregarding your schedule, have a talk wth him about it and if he refuses to cooperate, then go the principal. About the illegal activities, I am not sure what you are referring to but if iit s personal and does not involve harm to minors, its none of your business...