For children - an excellent booklet is available....

....from the MTO and Ontario Cycling Association: the "Young Cyclist's Guide", teaching about safety aspects of riding. It's done on a child's level and is very readable by even a 9-year-old. It's used in print format by some CANBIKE courses and is available online at:

http://www.mto.gov.on.ca/english/safety/cycling/youngcycli...

Here's its index:

What's Inside

* Getting Ready to Ride On Your Own
* A Bike is a Vehicle
* Use Your Street Sense
* Signs of Safety
* Staying Away from Trouble
* Handling Your Bike
* Protect Your Head
* Ride a Safe Bike
* ABC Quick Check
* Other Important Information

If you have a child that is riding, sit down with him/her and read. Jump around and see what's of interest to the kid - the pics are funny and actually one learns something from looking at, thinking and talking about what's shown....