Begin by browning ground beef in a skillet on the stove top. Drain beef after browning and add to slow cooker.
Add ketchup, mustard, onion powder, garlic powder, Worcestershire sauce, brown sugar and salt and pepper to meat in slow cooker and stir well. (Kids love this part - let them dump everything in and stir away!)
Set slow cooker to low and cook for 4 hours. Serve sloppy joes on your favorite hamburger buns. That's it!