Most of Mercedes' alphabet flashcards and books have both uppercase and lowercase letters. I wanted to introduce this concept to her in a fun way. We wrote the upper and lowercase letters on Easter eggs. I told Mercedes that each letter had a mommy and a baby. We separated the tops and bottoms of the eggs and then "helped the mommy letters find their babies". She doesn't recognize the lowercase letters yet but she understands the concept, and she loves the game of matching mommy and baby letters!
Idea from: http://rubsomedirtblog.com/2011/05/same-old-eggs-new-twist/