Glad to hear from a fit minded grandmother. For instant action let me recommend you visit “ChooseMyPlate.gov, a USDA site with lots of free materials you can use right now to educate your kids.
There is something for everybody. Follow the TEAM NUTRITION thread and you’ll have access to even more materials.
Also, check out American Council on Exercise’s ACE GetFit. Click on Youth Fitness for more excellent free materials for children and youth. ACE’s Public Outreach page has more programs you can take a look at.
These materials are designed for educators such as yourself and I’m sure you’ll be able to glean a lot of material from these sites to help you get informed and started right away. You don’t have to be a personal trainer to benefit from and use these materials to educate your kids.
I also highly recommend you take a look at ACE’s Personal and Group Exercise training certifications as well.
Go get’em Janet and more power to you! We need all the “Grandma’s” on the side of fitness we can get! I’m one myself.