You have 10 and 11 year olds together? Our 10 year olds are Webelos and they become Boy Scouts when they hit 11.

Personally, I wouldn't worry too much about it. At 10 and 11, they are very picky. When they are 12, they start to open up. By 13 or 14, they eat anything placed in front of them, and then some. Last year when I was teaching Wilderness Survival, I showed them a log with ants and said they could eat the larvae. I didn't ask them to, but they ate a bunch of it. They were hungry.
I also wouldn't worry about it because you aren't taking them backpacking. You are just prepping them for being a scout. Showing them real simple meals is a big help. Whether or not they actually like is secondary. They just need to see that it can be easy to cook outdoors. Of course, if you follow the advice already given, they will probably like it. laugh

As a scoutmaster and looking at your position, I don't see much you can do to prepare them more. Their complaints of cold, wet, hungry aren't a reflection of their cub scout training. Boy Scouts is were they learn to not be cold, wet or hungry.
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