Re: Teaching front rolls
Brian - what I would suggest is what I think I call "horses" - the patterning of break falls. Do that for several months if necessary - don't even consider front rolls.
Do the head hold while doing "slither" break falls.
Do low koshi-nage. (that's how judo kids start)
When you start with the rolls, challenge the kid to count your fingers, look you in the eye and tell you her birthday, etc.
Also, they should be so used to breakfalls/hip falls, that the arms do not feel like you are "putting them on the ground to roll" - rather, they literally feel like they are wrapping their arms around the invisible body that is throwing them, just as in koshi-nage.
I think that being "thrown" by the arm is neurologically confusing, compared to being "thrown" by the core. The latter feels like its happening to you, whereas the latter is too far away. One doesn't know what is happening to one's body, unless you really get torqued from wrist to core - and that can be dangerous for kids, both due to the bone-plates not being sealed, and in not being able to read the threat and take the ukemi.
That's why I've always tried to teach that one should keep one's hand/arm close to the body. (aside from how dangerous it is to allow one's arm to be twisted and extended).
Nage should therefore be training on kaeshiwaza from day one - this positions their body correctly for ukemi.