I help out with the 2-3 year old room for a MOPS meeting once a month. One of the fun things that I do with the kids is have them all sit on the blue rug that is in our room and we sing songs.
This age group just loves to sing already but to make it even more fun I usually tell them right before we start each song to sing REALLY loud if they know the words. This gets them even that much more involved.
One time after the meeting I heard one of the little boys telling his mom that they sang really loud. I think it is cute that even at such a young age they remember things they did and share it with their parents. Of course, this particular time the mom was kind of looking at her son with a strange face trying to figure out what he was talking about. Once I explained to her what he was telling her I think she thought it was cute.