Preheat the oven to 375 F. Grease an 8 x 8 glass baking dish and set aside. Toss together the rhubarb, strawberries, cornstarch and granulated sugar until coated. Dump the mixture into the greased baking pan and set aside.

In a medium bowl stir together the flour, oatmeal, brown sugar, and salt. Cut in the cold butter with a pastry blender, until it clumps together into crumbs. Top the strawberries and rhubarb with the crumble.

Bake in a 375 F oven for 30-35 minutes or until the crumble is browned and filling is bubbly. Serve warm with ice cream or whipped cream.