Peel apples; slice the “cheeks” off of the cores, and discard cores. Slice apples into 1/4-inch slices, place in an 8×6-inch (or similar) baking dish, and toss with lemon juice and maple syrup. Taste a slice, and see if it tastes sweet enough; if not, add a bit more maple syrup. Set aside.
In a medium bowl, combine flour, oats, brown sugar, almonds, and cinnamon. Using your fingers, work in the butter until the mixture resembles wet sand, and it sticks together in clumps. Taste, and add more sugar if you think it should be sweeter.
Pour topping over apples in the baking dish. Bake for 22 minutes, or until topping is golden brown and apples are just tender. Cool for 10 minutes before serving. Serve with vanilla ice cream for extra oohs and aahs.