Glass is a magic thing that is both solid as a wall and clear as the air. It starts out as sand and with tons of heat, and a few key ingredients, it becomes the super useful material we know and love. In this episode we look at how glass is made, why it's clear and how nature  makes glass too. Plus, hear about Sanden's latest invention and guess the all new Mystery Sound. This episode is sponsored by <ul><li>Indeed (<a href="http://indeed.com/BRAINSON" class="c-link">Indeed.com/BRAINSON</a> - to start hiring now. Terms and conditions apply. Cost per application pricing not available for everyone.)</li><li>Shopify (<a href="http://shopify.com/brainson" class="c-link">Shopify.com/brainson</a> - for a free 14-day trial and full access to Shopify's entire suite of features)</li><li>Outschool (<a href="http://outschool.com/brains" class="c-link">Outschool.com/brains</a> - save $15 on your child's first class)</li><li>Bombas (<a href="http://bombas.com/brainson" class="c-link">Bombas.com/brainson</a> - Get 20% off your first purchase.)</li></ul>

Get a whiff of that: Why you smell like you

Brains On!® is a science podcast for curious kids and adults from American Public Media. Each week, a different kid co-host joins Molly Bloom to find answers to fascinating questions about the world sent in by listeners. Like, do dogs know they’re dogs? Or, why do feet stink? Plus, we have mystery sounds for you to guess, songs for you to dance to, and lots of facts -- all checked by experts.