In a large covered pot, steam the spinach in water that clings to the leaves until just wilted, 2 to 3 minutes. Drain and chop the spinach and set aside. In another pan, sauté the scallions in the oil for about 5 minutes, or until softened and slightly brown.
Preheat the oven to 350 degrees F.
In a large mixing bowl, combine the spinach, scallions, rice, dill, and lemon juice. Add the salt and pepper to taste. Mix ingredients together well until the mixture holds together.
Prepare a baking sheet with cooking spray or a light coating of oil. With damp hands, form 1/4 cup of the rice mixture into a firm, round ball. Roll the ball in the breadcrumbs and place on the baking sheet. Continue with the rest of the mixture, placing balls about an inch apart.
Bake for 20 to 25 minutes, until the balls are heated through and crisp on the outside.