Your riders will definitely appreciate the way this song starts out slowly and then builds into a steady climb. At first listen, you may not think this song would fit in a cycling class, but once you've tried it, you'll want to go back to it again and again. It's Green Light from Lorde's upcoming album Melodrama (expected to be released on June 16) and I first caught it when she performed it live on SNL a few weeks ago.
There are a few different ways you may want to use this one. It starts slow and picks up a beat at :49. I recently used it after a particularly hard sprint, so we took the first 49 seconds as a recovery before a steady (65 rpm) standing climb. If you aren't needing that recovery, you can ask riders to climb in the saddle for the first 49 seconds and then bring them to a standing climb once the beat picks up, or keep them in the saddle to climb the entire song. You have quite a few options here but any way you choose, I'm sure you and your class will love this one!