OK, let me try a review on my cycle lights. The ones I have are from Tesco, OK Tesco do not actually make them, and I can't find any manufacturers names on them, but they are available from Tesco, as well as thousands of other places.
Mine are LED ones, and I have the choice of static light, flashing, or a "Night Rider effect" because there are actually three LEDs in eacjh fitting. Legally speaking, the static ones are the only road legal ones, but the Police assure me that they are only interested in cyclists being seen. The lights require two AAA size batteries, and of course you can use rechargable ones. They come complete with a mounting clip that fastens onto the bike, and the light simply slides onto that. This means you can remove the lights in a few seconds, even when parking your bike up to go into a shop!]
I can not remember the price I paid, but these are really cheap nowadays, so there is no excuse for not having them. Too many people get injured or even killed on cycles, usually it is down to them not being seen, and these lights mean other road users instantly know you are there.
If your kids have bikes, please make sure you have them fitted with lights, in the event of an accident, it will be too late to reconsider!