Are bells muktzeh?
Does the presence of bells on a toy make it muktzeh?
Here are two types of bells in question:
This short article addresses the general problem of bells on Shabbath, and yes they are prohibited for adults to use.
However, this answer addresses toys that would otherwise be Muktzeh and explains that, if they are essentially children's toys, they are not Muktzeh for adults. I should add, though, that I've seen in the Sefer Shemirath Shabbath KeHilchathah (need to find source) that this assumes a child is likely to actually play with it. SS"K (16:2) also states that, although one may give a rattle to a baby, one may not shake it to make noise.
In a nutshell, yes, bells are Muktzeh, but bells in children's toys may not make the toys Muktzeh, depending on the likelihood that a child will actually play with the toy in question.