Welcome back to SciShow Quiz Show! In this episode Hank will be competing with older brother John Green in a battle of science related trivia on behalf of Subbable subscribers Anna Dilley & Andrew Villarreal.

Howcast - The proper method for cleaning any antique clock depends on the clock's age, but there are general rules to follow.

Howcast - Native Americans, and others, have used the branches of the elderberry tree to make musical instruments since ancient times.

So we know that dendrochronologists study tree rings, but how do these form? Do they form in precisely the same way all the time? They don't, which provides enormous challenges for any researcher. In order to properly construct a...

Plants: The Internal Structure of Dicot Stems: This clip describes the roles of important internal structures present in the stems of Dicot plants.