I was going to suggest smoothies for breakfast, frittatas and the likes for lunch. check out the naturopaths kitchen and janella Purcell. They do alot of gluten free recipes and janella is doing some lunchbox ideas ATM.
I'm coeliac and was diagnosed when I was 10 years old so have lived through childhood with the disease, which informs my perspective I guess. I tend to just buy from the health food section in the supermarket, but I haven't checked out the sugar content. I think there maybe some more plainer things like puffed rice cereal.
In terms of the bread, it is an acquired taste. Try a few recipes or different brands (if you can get different brands). I found starting out with using it as toast was better than launching into the taste via a sandwich. The bread also tends to crumble really easily so it can get a bit messy. I found it a bit embarrassing when i was a kid that my sandwich would break up in my bag or large sections of crumbs would drop. I think the idea of frittata or something like that might be a good option. At school I found it was about trying to fit in with my food so I probably wouldn't have wanted to deviate too much from what other kids were eating.
These days most products have a replacement or equivalent in the health food isle which is a social life saver as a child.
I feel for you and your son as I'm coeliac and my son also holds the gene but so far hasn't acquired it.
I would look at moving away from breads and cereals. there are some ok options - especially if you can make your own - but on the whole they aren't very good.
Eggs, baked beans, dinner leftovers (yes!) work for a more filling breakfast. Also, GF savoury muffins are an option for something bready - just keep them in the freezer if you have extra.
I can't help with food ideas, I can help where to go. There is a shop called Gluten Free in Ormond, you can order online. They have a heap of gluten free breads and so on. Another place is in Werribee called Absolutely Gluten Free.
I'm also GF and have been eating the Basco GF breakfast cereals. I also make my own bircher muesli. I'm having other issues though and have finally bought the GAPS Diet books, including the recipe book. There are nut free options. I'm thankful I have a TMX, as it makes things easier and also cheaper - I can make my own flour, for example.
You can make things like egg & bacon fritatta muffins and freeze them. I eat corn thins or rice cakes for sandwiches or make my own GF bread. I'll PM you the links. Otherwise google Bread in 5 Gluten-Free Crusty Boule.
I'll also dig out a grain free, nut free pancake recipe for you.
I highly recommend you investigating the GAPS Diet.
My SIL has a sister & bil who coeliac's disease and she said she uses normal recipes and just changes the flour and marg etc.
Coles also has a bread mix that they said was the best one they have found and not that hard to make.
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