K- 2:

I'm attaching a link to a great "Ant-man" workout. This is a circuit style workout with a total of 9 exercises. I would suggest two rounds of the circuit for a good sweat, but you can do as much as you like.

Or...

Go outside and play! I've you haven't tried making your own obstacle course yet, give it a try! Be active in any way that you enjoy that gets your heart rate up!