Personally, I have been using heartmath products for years now. When my anxiety was at a bit of a high and I was reading up books upon books and doing hypnosis and other relaxation therapies I discovered HeartMath. They say the universe always looks out for you and it certainly does.
I found the heartmath innerbalance to be a godsend and a great tool for children too. Trying to get kids into meditation can be quite a task but if there is a cool gadget involved then it is much more fun.