My university campus store offered a molecule kit and it was awful and confusing to use so I went looking to amazon for a replacement. I found this set because of the reviews and it is everything I wanted it to be and more! The kit is EASY to use and the pieces snap in without a lot of force needed (there is even a removal tool in case there are any issues) and there is a booklet inside that has a key to what colors represent what atom. The kit had more than enough pieces for a 300 level Organic Chemistry class and I had a lot of fun building complex molecules for fun without running out of pieces as well. Excellent kit all around and I recommended it to several other students who fell in love with it too.