Are you cutting back to save for something special like a vacation or new car/ frig or whatever, or trimming down the budget due to financial needs. I would get them involved in the "why" we are cutting back, and have them help with meal planning, grocery shopping, clipping coupons, learning about sale flyer, seasonal items, and how to plan and stay on budget, these are skills that they need for life.
Fast food is fairly easy to mimic -Big Mac, thousand island dressing, cheese and some shredded lettuce will do the trick, make them like sliders and the kids will love them.
Chicken wings, with carrots and celery, ranch and blue cheese, you could also add in some loaded fries.
Nachos - my family loves shredded pork covered nachos, we use to get them at the Braves games. So now I make a big pork roast Shoulder or Boston butt, I get a big one so I can freeze the leftovers for pork nachos. When they see them we start talking about that time we went and this or that happened
Spinach dip is easy to make you can add in canned crab, or salad shrimp, artichokes, bake in the oven 350 till bubbly.
Make your own Tacos and you can go in a lot of directions with this, burritos, use chicken , pork...There are lots of recipes on burrito casseroles
Think about presentation, I have done this a couple of time, we love to draw on the butcher paper that they put on the tables like at Macaroni Grill, so I have made lasagna, or stuffed shells and used the white side of old wrapping paper and throw some crayons on the table, turn off the TV, and no Phones.