Do it all at once (IMHO). My younger one was much easier to tranistion than my older (5yr) one. I did make some sweet raw treats to help with the transition. Green smoothies are a great way to get greens in (as fruit is sweet and what child refuses sweet fruit?). 60% fruit 40% greens. There is an article on this board called ODE TO GREEN SMOOTHIE by VVictoria Boutenko. WONDERFUL! My children have always loved fruit smoothies (which was first). I made it fruit till noon. Then lunch was next to be raw. Alison included raw veggies with lunch then made lunch all raw. We just went all raw. This is usually a green smoothie now (but before it was veggies with nut dips). raw snacks inbetween of course - cookies and candies and dried fruits and nuts etc. Dinner is a huge salad (usually a blended salad for the younger ones). Although my 21mo now likes to eat salad just like mommy. Then a bit of cooked (although I am very quickly making dinner all raw too - my kids LOVE Alissa's recipes).