This blogger says the best age to start is 7, but has plans or kids as young as 5. I want to teach my boys how to play the piano when they get a little older.
basically, if you're going to teach piano to your own kids, set aside a time for it and be serious about it. Keep distractions away, set a time and treat it as if you were sending her to lessons (i.e. don't set other events for that time, it's LESSON time)
Wanting your kids to learn a bit of piano? Definitely check out this delightful site! Joy is a pianist and teacher in Ohio with great passion for helping students experience the wonders of music making! At her blog/site Color In My Piano, she enjoys sharing and exchanging ideas and resources for piano teaching. Many great sheets, aids and lesson ideas for teaching music and piano here!