i prefer the top two over the bottom mainly because the bottom one looks like a pharmaceutical logo. the next question i would have to ask is what kinda dance is he teaching? i only ask because dancing ranges from very strict traditional to very modern and free flowing. if its a modern dance you're heading in the right direction.. if its classical- start over. the first thing i noticed about the whole piece is that its very flat. it looks like the opacity on the whole image is dropped to 60%. the colors are very washy and faded, they need to be rich to give it some life! i like the choice of colors in the top left one but it looks like it was printed on a piece of paper and left in the sun for a month :p the composition isn't bad but i think the colors are struggling. hope to see an updated one!

the first two look like clipart, almost like they could have come right out of the corel draw clipart book.

the third one looks nothing like dance.

Sorry I agree with gwells, I really don't think these logos are working right now, even though i like the first two logos, they would look better in a poster, or something else, and the one on the bottom doesn't work at all.

What I think you should do is work more with the type, to give it a feel of the kind of music that is been danced.

Check logopond for ideas