Mindblog links to this interesting study, in which children around the age of 4 were taught a procedure (like retrieving a plastic turtle from a puzzle box) which included actions that weren't necessary to complete the procedure (like saying a magic word or making a particular flourish).

Children tended to mimic the irrelevant actions, and the interesting part is that their tendency to continue to carry out the irrelevant actions, even when taught later that those actions are irrelevant and instructed to not carry them out, tend to persist.

Chimps apparently don't do this, so human children are much more adept at copying adult behavior, and it seems like it has a lot of traction...it's very difficult to undo the original training. A commenter at MindBlog points out that this might have ramifications not only for learning tool-using procedures, but also for the adoption of ideologies like political and religious affiliations. I'd guess that studies have already been done regarding the degree of correlation between children's political and religious beliefs and their parents', but that would be interesting stuff to look at, especially if they carried out a long-term study to rate how often those views diverged, and what factors influenced change.