For Tai Chi at home, try a great teaching video from Juan Li (video is in Spanish), a well renowned instructor (
http://www.ichingdao.org/tao/en/biography-of-juan-li.html). I have the entire video (35 minutes or so) and can share it to anyone interested (as it's old and very hard to find). Just mail me. I use a transfering website that gives you 10 days to download big files uploaded by others (
http://s214.transfer.ro/)
Juan Li explains the movements very nice, guiding you all the way. The Tai Chi 13 Steps is easy to follow.
The initial training, which you can do with you kids, is exercising different types of walking:
- walk like stepping on clouds
- then walk like stepping through mud
- walk like stepping into water
etc.
to exercise the way you feel your feet and movements on different types of ground. This will make it a funny experience too. For kids, explain how you feel when walking like that: clouds are fluffy, soft, mud sticks to your feet, water puts pressure on your feet and so on and so forth.
http://www.youtube.com/v/D9uLsYDDBqA&rel=1If you want to get deeper into Tai Chi practice, try
http://www.amazon.com/Inner-Structure-Tai-Chi-Mastering/dp/1594770581/ref=sr_1_1?s=books&ie=UTF8&qid=1298706912&sr=1-1 - a book that explains the other side of Tai Chi - but this is just for mastering Tai Chi movements at an advanced level.
Hope this helps,