Preheat your oven to 350°F (175°C) and line a muffin tin with paper liners.
In a large mixing bowl, combine the grated zucchini, mashed bananas, maple syrup, melted coconut oil, and vanilla extract.
In another bowl, whisk together the whole wheat flour, baking soda, baking powder, salt, and ground cinnamon.
Gradually add the dry ingredients to the wet ingredients, mixing until just combined.
Divide the batter evenly among the muffin cups.
Bake for 20-25 minutes, or until a toothpick inserted into the center comes out clean.
Let the muffins cool in the tin for 5 minutes, then transfer to a wire rack to cool completely.