REI has their "Passport to Adventure" Program that is free for your kids. They have an adventure journal for your kids to fill out on the trips you plan and go on as a family. When the kids tell REI about their adventures, they'll be able to get free prizes.
Here is the link for the Adventure Program http://www.rei.com/family-adventure to learn more or check out at your local REI store.
(Thanks to Freebies2deals.com)