This is a good place to start reading. Big 3 Buyers Guide: The Big 3 refer to Sleeping bag, Tent and Backpack. These typically are the heaviest bulkiest items in many peoples gear list. huge weight savings can be had by paying close attention to these. Allot of people have a big 4 list which adds in the sleeping pad.

This "Gear List" was put together by a Troop from California. There is allot of great information available here. I think most of the weights are a great guide as too what to aim for. 20 pounds pack weight is a awesome goal. The main discrepancies with our region may be the use of tarps and the kids using down sleeping bags.