This was THE HIT Christmas morning.  I'm so glad I got it.  I wasn't sure about it because of other reviews, but the learning application possibilities was too tempting for me.  Our 4 1/2 yr old is fascinated with the body and how it works and is always playing doctor.  She was so excited to put all the 'guts' on the matching sheet, so her and her dad did that while I festiduously assembled the clear body case (which is the worst part and gets the worst review).  Knowing going into it, that it would probably not match up good, and the tabs would likely snap off, I was prepared for disappointment, but hopeful.  Unfortunately, the reviews on the clear case are accurate.  Although I didn't break any tabs, I can see how that would easily happen if you weren't careful.  And it must be the type of plastic or something, that it warps a bit??? All in all, it's a GREAT learning tool for inquisitive young minds and I'm sure it will come in handy down the road for science, health and biology projects.