This is one of the best purchases that I have from Amazon!  I love it so much that I ordered another one as a gift for my niece.  My 4-year-old daughter LOVES it so much and she enjoys the "organ-izer" game (she calls it the "matching game").  She already knows the anatomy terminologies more than this model offers.  For example, she knows the strongest muscle is the cardiac muscle and heart is about the size of a fist that has four chambers.  We have been getting other human body books for her and she has learnt so much.  I think this human body model is great to help initiating the interests of little ones.  My daughter says "mommy, I know there are two types of bone marrows - yellow for storing fat and red for generating red blood cells, white blood cells, and platelets."  She can't wait to learn more about human anatomy and physiology every night at bedtime.