They don't click on hard they sit on which is easy for the baby or toddler to take them off. Like if I held one upside down the top would stay on. But easy enough to glide off. Hope that helps. ((some of mine stay on better than others))
The eggs are like hats. They don't snap or anything. The toddler just puts them on top of the "chick" that has the corresponding facial expression. When mine tries to pick up the container with them all in it, and she turns it upside down, the eggs all fall out and come apart. She finds it funny, but it becomes kind of tedious to put them all back in (if toddler doesn't want to clean up after herself). That being said, the tops of the eggs fit each egg well (there are no gaps) and it's easy for a baby to take them off and put them on, even if the faces aren't aligned with the chick (or on the correct chick).