Preheat oven to 425. Rinse scallops and drain well. Beat egg with small amount of milk. Dip each scallop in egg mixture and then in cracker crumbs. Set aside. In a small pan add 1/2 of melted butter add mushrooms, saute for 2 minutes. Remove from heat. Add the rest of the melted butter to a baking dish. Add scallops and mushrooms, lemon juice, salt, pepper and garlic powder. Bake for 15 minutes.