Preheat oven to 350 degrees.
Grease or line 12 muffins tins. Set aside.
In a blender, combine bananas, yogurt, oil, eggs, vanilla, oats, baking powder, baking soda, and cinnamon. Blend well.
Stir in zucchini and chocolate chips. Pour into prepared muffin tins. They will fill a little over 3/4 of each muffin cup in a standard muffin tin.
Bake for 18 - 22 minutes or until toothpick inserted into the middle comes out clean. Sides will be brown - tops may not brown.
Allow to cool slightly, then remove from tins. Cool completely on a cooling rack. Store in the refrigerator or freezer.