Kids seem to enjoy the novelty of these. You can customize the packets as needed, leaving onion out of those who dislike onion for example. If you've got smaller kids, make smaller burgers of course.
Mix the beef, egg, bread crumbs, lemon juice, seasonings, and cheese.
Tear some foil pieces large enough to fold in half, but the burger on, then wrap tightly and seal. Shape 4 patties and place one on each piece of foil. Place onion, potato and carrot slices on top. Top with 2 pieces of bacon. Wrap the foil tightly around the meat and vegetables. I like to bring two pieces up to the top and fold down a few times to create a nice seal, then roll the side pieces up.
Bake at 350 for 45 minutes or place them on the grill or in the coals if you want to cook outside.