I used to teach 5th grade and was faced with the same challenge. The best wisdom I can share is that the standard alogorithm comes up naturally during sharing discussions, usually because a parent has shown it to a kid. We would discuss how it works when it comes up. We introduce the algorithm as "a way the kids should eventually know" in the end of 4th grade and it comes up again in 5th. One methid that I saw and like was to combine arrays to illustrate the way the multiplication algorithm works. this really helped some kids get the idea. This is a very sticky issue. Good luck,
