I gave my 4 year-old my Romisen RC-G2 non-q5. He likes to play with all my lights, but that one seemed big enough not to swallow, small enough not to clobber someone with - can you imagine a preschooler with a 3 C Mag in his hand???? - cheap enough not to worry if it disappeard, and silly me, I thought it wasn't bright enough to really do any harm, if left on, or if he accidently shone it in someone's eyes.
Well, after having him accidently shine it in my eyes a few times, I reconsidered. I had warned him not to shine it in his eyes, and though I never saw him do it, you just know kids at one point or another will take a light and stare into the emitter and go "cooooooool...." you know you did this with your old 2 D incans, then Maglites, 30 years or more ago, heck some of you have done it with your LED's (but I'll bet, only once.) If they try that with a bright LED today, they'll be saying "ouch!" and their ophthalmologist will be saying "retina damage."
Now I've got the RC-G2 back and he's got an E01 and some fauxtons, both white and red. He's well past he stage of putting things in his mouth, so i'm not concerned about the size, and I think it would be much harder for him to actually harm his or someone else's eyes with these lights than with the much brighter, and more focused beem of he RC-G2. Though I suspect even these could do some damage if you stared right into the emitter for an extended period of time.
Maybe the old incan Mini-Mag is the way to go. And you can get a color the kids like.