How can I help my boy dancer deal with stereotypes?

It is so good to know that your son is a dancer. Dancing and other performing arts provide children with a way of expressing themselves. Children involved in performing arts are usually quite creative and sensitive. He is so lucky that you as parents have supported him to follow his passion.
We all live in a diverse world and people are not always very supportive. You should encourage your son to take these – not so positive responses – as an opportunity for self-development. School is a miniature society, learning to stand up to his ideals and dealing with conflicting responses with confidence will prepare him for practical life.
Let him understand that at this point of development, he should shift his locus of control from external to internal. In childhood comments and views of others shape our personalities, but as we grow older we need to develop our own sense of right and wrong. If dancing makes him happy, he should follow his heart. For a happy and contented life it is very important that he respects his own choices.
It is the right time that he learns to accept difference of opinion openheartedly and at the same time learns to practice assertiveness when required.
Best wishes for your son.

That’s so sad to hear that your son is the subject of those comments.
It’s so important to encourage your son to be themselves, and to enjoy what they love. The more his self esteem builds with his dancing mastery, the more he will connect with like minded friends and likely that the comments from others will reduce or not impact him. It might also be handy to see if the school cater to his dancing needs where he might find a safe group to connect and dance with while at school.

Oh, I am so sorry to hear that! Kids really are cruel.

Your son sounds very talented, and I am sure that he gets a lot of self-confidence from his dance.

I imagine that it is hard to ignore and "turn the other cheek" to these comments. I doubt there is a way to make other kids' ignorance and insensitivity disappear.

What kind of dance does he do? If he does any type of hip hop or has some gymnastic type "stunts" or jumps, this may help to make his dancing seem "cooler" to some kids. If he does perform some of this type of dance, perhaps he can showcase it at a school talent show. I'm sure that the kids would be impressed.

Once he gets to high school, the majority of the kids are more accepting of different personalities and should get better. He can then tap into the theatre group kids and have his own "people," which will make him feel much better.

I genuinely wish him the best in this hard situation. I hope that he has some good friends to hang with in the meantime.