You should start with this book.

http://shop.nationalgeographic.com/product/995/169/993.html

It is nice that you guys are trying to incorporate geography into every day curriculum. For most schools though geography is not part of core curriculum which is a real shame.

Geobee is mostly an individual endeavor. Kids study maps, globes, read national geographic magazine, study random facts about different countries (culture, politics, history, and of course, geography). They really have to love these things in order to do well.

GeoBee website gives 5 questions every day. The teacher can use that to give kids daily quiz. It is a good way to build an interest in geography.

http://www.nationalgeographic.com/geobee/ax/newquizstart.html

Another thing that you can do is to teach your kid map reading. Ask him to give you directions by reading map while you are driving. Map reading skill is critical in winning Geobee as well as useful in daily life.

Boys are naturally better at directions and maps. This may have something to do with our history as hunter-gathers. Girls may need some encouragements to participate or continue to participate in Geobee. But it should be very positive experiences for all kids.