Kids over 5 can now get a COVID vaccine in the U.S. We know a lot of you have been waiting for this day and lots of you have sent us questions about the vaccine since the pandemic started: like what's in the COVID vaccine? How does it work? How do scientists know it's safe? And even if the vaccine isn’t available to you where you live yet, this episode will answer those questions -- and there are some fun games you can play along with us!

If you have more questions about how COVID, the vaccines or anything else, you can send them to us here.

Plus we've got some tips for how to distract yourself if you're feeling nervous, and an original song designed to help you shake that arm after the shot so it doesn't get as sore. Dance those ouchies away!

Also: Three (3!) mystery sounds and a Moment of Um that answers the question: How does concrete harden?

And you can learn more about the vaccine trials for kids in this episode:

Vaccines for kids and silver linings: Our second COVID summer