I think we should assume kids are starting from scratch, except when it comes to normal school clothes. Also, I don't think we should target the 12-18 year old age group for this, as that gets up into adult sizes. I am going to focus on the 12 year old, from 3 percentile to 97 percentile boys. That is from 4'5" boys up to 5'5" girls.

Finally, we MUST assume these kids will hike 20km a day, otherwise WE are off on the wrong track!

Growth Charts
http://www.cdc.gov/nchs/about/major/nhanes/growthcharts/html_charts/statage.htm

Mark Verbers page on sleeping systems
http://www.verber.com/mark/outdoors/gear/sleep-system.html

I'm going to tackle the sleeping bag issue first, and update later. When we say 'easily reaches 20degF' I will assume it can get lower but will outfit for 20degF. That calls for 2" of loft, but not neccessarily a 20F rated bag. One problem however is finding a bag to fit the kid. There are fewer kids bags out there than there are kids sizes. A 5' kids bags might work for 50% of 12 years, but too small for about 40% and too large for perhaps 10%.

These might fit 50% of 12 year olds...

This one is 2" of loft, and only 1.2 pounds, but at $190 out of our price range.
It's also probably too roomy for most kids, but you might fit two in. <img src="/forums/images/graemlins/smile.gif" alt="" />
http://www.westernmountaineering.com/ind...mp;ContentId=73

This one is >2" loft, and is 2.3 pounds for $80 which ain't bad.
http://www.backcountry.com/store/MHW0846...C_ID=WR_MHW0846

Or, why not make something to custom fit your kid?
http://www.questoutfitters.com/fabric%20lightweight-cart.htm
Nylon shell on outside, 2 layers of Primaloft, fleece on inside...
1.1 UNCOATED RIPSTOP 60"x 1.5yds 2.8oz for $11.25
4oz Primaloft Sport 60"x 4.5yds 30.0oz for $44.78
5.9 oz Fleece 100M 60" x 1.5yds 14.8oz for $16.13
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3 pounds for $75
That is actually about 2.5" of loft, top and bottom, which is overkill.


Good clothing for 20F and still hikable for 20km will add up, $-wise, unless they shop around. They could get by with what they might alread have for school, but the smaller ones will really be unneccessarily encumbered unless if they get dressed my their mother, unless they go with something like this...

skin layer - normally packed
200wt fleece pants - normally worn
underwear - this I will leave to their mom
skin layer top - normally worn
wool sweater - normally worn
LIGHTWEIGHT nylon rain jacket with hood and pants - normally packed
wool socks.wool mitts. wool hat. wool neck tube