WATCH: Here’s Nick Jonas Getting Freaky with Some Shapes on ‘Sesame Street’

Geometry makes his falsetto flutter.

Nick Jonas is journeying back to his roots of child stardom to perform an original song about shapes in honor of Sesame Street’s 46th season on HBO, but it seems that he’s can’t shake the sex appeal of the “Chains” that he’s been toting around as of late. Here, Jonas sings “Check That Shape” with Bert, Cookie Monster and The Count to teach you how to classify shapes.

Nick Jonas’s Theory on Shapes:

1. Pentagons – Have five sides, are “so fine”, drives you out of your mind

via GIPHY

2. Octagons – Are “blazing”, are “amazing”, have eight sides

via GIPHY

Watch the full video below, and catch his episode of Sesame Street when it airs on Saturday, May 21.