Chalk It Up to Toddlers

I took these pictures to document the phenomenon of kids eating strange things even though they often won't eat the perfectly good and delicious food you offer them at meal and snack times. On this particular day, David John and Benjamin thought it might be tasty to sample a wide variety of chalks.
Here is what your mouth might look like if you tried, say, blue chalk:

And here is Benjamin offering a delectable purple:

This is his terrible face when I tried to fish a large chunk of purple out of his mouth:

Finally, David John, even though he cried heartily after the blue chalk incident, just couldn't help himself and also tried the yellow:

This made we wonder, "Is this Pica?", "Are they suffering from acidic stomachs?" Maybe I should start offering Tums with every meal...