How do one keep positive in the classroom when the normal clever kids are really being stupid?

Sometimes if you can find a way to connect/bond with the kids through a fun but educational activity, that may change their attitude. I taught HS English to standard diploma seeking kids who were in special education for learning disabilities and behavior disorders. They were unmotivated, had practically given up, and were hard to engage in anything. One of the curriculum requirements was that they had to memorize a poem and recite it. I let them pick any author and they could act it out, draw illustrations to go with it, or provide some other way to enhance their presentation. I'll never forget the 6 foot 3 , 300 pound football player who chose a Shel Silverstein poem about being eaten by a boa constrictor as he acted it out. This tough, mean kid had us laughing as he shook off that tough exterior. All the kids participated (unusual for this class), and they seemed to really be more into the class after that. I tried other activities that infused creativity into the projects, and that really helped. Some kids are really tough to reach, so you may have to try other means.

I think that your question can be taken several ways. If the students are acting stupid, it could just be their ages and maturity levels. This is just their personalities. You cannot change that. They must grow on their own time. Part of being a teacher is accepting or even enjoying the crazy antics of kids. All you can do is redirect their attention to something exciting you are about to teach.

If you are saying that they really don't understand what you are teaching, then it could be a ploy or maybe they really don't understand.

Probably the kids around you are just brought up the wrong way. i would suggest what i have done. I had the same problem but I injected my positive atitude and everyone stardted to feel brighter and started to actually study.

Keep them occupied, find an attention grabber to get them focus or give them an extra challenge in either the form of a worksheet or board work.

just do something for yourself in class...

don't pay to much attention to the others

Just give them a killer smile.