Anal about chalk?

When Jack was a baby, Keith used to let him sit outside on our back patio and eat sidewalk chalk (and crayons, but that is a whole nother day...). I used to say, "What are you thinking? Don't let the kid EAT that chalk!!"

Now, Jack wants to color with chalk almost every day, but what to do with the little one?

Let him eat it, of course.

Plus... he mostly just chews on it... he doesn't really swallow?!?!