Preheat the oven to 350 degrees F.
Put the ground beef into a mixing bowl. Measure 1/2 cup of the rice and put it in with the meat. Mix it all together with your clean hands. Form the mixture into 8 or 9 golf ball-size balls.
Cover the dish tightly with foil and bake for about 1 hour. The rice in the meatballs will have puffed up all around the meat, and your meatballs will look like little porcupines!
Cook's Note: Let an adult help you remove the dish from the oven with oven mitts or hot pads. When you remove the foil, steam will come out, so be careful!