M.H.
I moved my 2 1/2 yr old to her toddler bed when she climb out of her crib, but even then I was worried about her roaming the house, falling out, staying in bed, etc etc. So, I took her shopping for her new bedding. I let HER choose what she wanted (Tinkerbell) and what kind of bedding. I even let her get a Tinkerbell throw. Well, that evening I went and converted her bed while she was playing in the living room. I washed all her bedding and set everything up. I then called for her to come up. She was SO excited about the bed, she jumped in, went under the covers and said "Mommy, I am soooooo sleepy"- it was only 7:15! She hasn't gotten out of bed and roamed or anything (I told her that if she got out of bed, the only room she could come to was mine and she's stuck with it - it's been 4 months now and she only leaves her bed in the morning when she wakes up). I think getting them involved in the transition as much as possible will really help. Good luck!