Here's an interesting (and somewhat gross) article about some semi-common kids health issues.  Apparently, the top four "grossest" ones include:

Pinworms, Lice, Ringworm and scabies.  The article goes into what each thing is, how it is spread, the "yuck" factor of each affliction, and how to treat it. 

I found the article on CNN in the health section, however the article itself seems to be sourced from Parenting magazine.  It's definitely an educational read with a solid yuck factor.