What are some cool babysitting games for four kids to play all together?

I babysit four kids, two boys and two girls:

Brenden-10

Alyssa-8

Jackson-6

Skyler-4

The girls like Barbies, and the boys like Lego!! I don't just want to play with the girls, and ignore the boys, or vice versa, but I can't seem to think of anything they can do all together! What are some fun %26amp; exciting games that the kids will Want to play? Please no games with lots of supplies or anything that's too complicated.What are some cool babysitting games for four kids to play all together?
Hide and seek, board games, write up a scavenger hunt for them to figure out to get to a prize (maybe their snack or a treat?), try making cookies or some kind of recipe (pizza crackers- spoon some sauce onto a cracker, add some shredded chs and a slice of pepperoni- all kids can make their own but it gets them around the table), "vet" (they bring you their stuffed animals and you check them out and make up problems and procedures), puzzles, try having one person hide an object in a room and the others have to race to be the first one to find it and whoever does gets to hide it next, um.., you can play 'superheroes' where they each pick superhero names and powers and you assign them a task, like to find the giant peanut butter man whos walking the streets sticking people together and they need to find him and think of ways to trap him and get the people unstuck and put him away somewhere he wont ever get out. When they are done you call them back and one at a time ask them diff questions, (so they arent all screa,ing out things) like "Alyssa, how did you find the pb man?", "Skyler, what did he look like?", "Jackson, where did you put him away?", "Brenden, how did you get the people un-stuck?" Then they go back to "work" in their offices until you call them (make loud beeping noises) with another mission. This works good when your trying to make dinner or something b/c they can run upstairs to get the villian or outside or wherever you say he is. good luck!