It is possible to cook up gourmet meals, but much harder when you are cooking for 5 and no one is helping you.
I woudl go super simple and not worry about veg and stuff too much -= buy a load of apples, bananas and carrots to snack on as they keep well.
Fresh tortellini with pesto - the packs keep for ages in the fridge, cooks in 3 mins, drain and return to the pan with pesto for give it a quick heat up.
Gallo risotto heat up water, add the risotto mix and heat for 12 mins giving it a stir. Easy peasy. NIce with a tomato salad and some parmesan cheese (take the 'dried hard Italian cheese' for camping ease).
Sausages on in the oven/BBQ with smash and baked beans and/or tinned peas.
Chicken in the oven with crusty bread and salad.
Chicken super noodles with tinned sweetcorn added. Also a soft boiled egg added is nice.
Tinned Stag chilli with rice, nachos and grated cheese.
'Spanish' stew - Fry an onion and some chorizo and a green pepper, add in 2x tin of toms, 1x tin of chickpeas or white beans and some spices if the kids will take them. Boil water and pour over 2 or 3 of the couscous packets (more expensive than buying a whole bag but much easier to just take with you). Serve the stew with couscous. Chorizo in a ring lasts ages out of the fridge.
Tinned minced beef with onions, add in drained tinned carrots when heating it up. Serve with smash and gravy if you like.