Here is a tip to save some money on the engines for the rockets. If you have a Michael's craft store near you they stock a decent selection of Estes kits, engines, and related stuff. They also run coupons in the paper every couple Sundays, watch for the 40% or 50% off on 1 item. Then go to the store and hope they have the "FlightPack" in stock. It is a box of 24 engines, ignitors, wadding and the little plastic plugs that hold the ignitors in. Usually goes for about $50-60, withthe coupon its $25- 35, or about a buck an engine. Sure beats 3 for $6.99.
It has a wide assortment of engines, so you can use a low power one to check the rocket / wind out,then Pump IT UP! if conditions are good. Don't forget to bring some baby powder to the field, dust the chute before you pack it, and pour a couple teaspoons in the body on top of the chute before you seat the nose cone. This helps the chute open ( no sticking together) and put s a nice white puff when it deploys so you can get a visual on it. Have fun!