7 post shaker

Okay kiddo, so a "7 post shaker" is a big machine that shakes things. It has seven "posts" which are basically big metal legs that hold the machine up.

Now, imagine you want to take a bunch of tiny pieces, like sand or gravel, and sort them into different sizes. You could use a sifter, but that would take forever! Instead, you can use the 7 post shaker.

You pour all the sand or gravel into a container on top of the shaker, and turn the machine on. The machine starts shaking really hard, almost like it's having a big tantrum! But that shaking motion makes the different-sized pieces of sand or gravel separate and fall into different bins.

So now you have all your sand and gravel sorted out into different sizes, nice and neat. And you didn't have to do all that sifting by hand!