Combine the first six ingredients and place in a casserole dish. Mix together the oats and flour. Add the margarine and brown sugar and mix well until the margarine is incorporated into the oats. Add the cinnamon.
Add the orange juice a little at a time until mixture is moist but still a little crumbly (you may not need all of the juice). Bake, covered, for 30 minutes. Uncover and bake for an additional 15 minutes until pears are soft and topping is browned.
Comments: Two of fall's finest fruits combine for a sweet treat.