I don't have any and I don't have kids but...
I keep my meals pretty simple.
I make salads for multiple days (chopped up lettuce, veggies) and use it for lunches and dinners. While I'm making the salads, I'll also fill small tupperwares with chopped up veggies for snacks.
I make beans for multiple days. There are bean casseroles which can be pretty easily prepared, popped in the oven and cooked. My staple though is a couple different can beans, can diced tomatoes, onions, garlic, some spices simmered on the stove.
I'll occasionally buy fresh veggies but frozen veggies are quick. You can roast them or simple steam them in the microwave.
I have a rice cooker which makes rice at the touch of a button.
On the weekends, I may take more time and make a dish but I always make a large batch so that I have multiple days worth of food.
I basically cook/prep food a couple times per week, usually less than an hour each time. It is pretty simple