Preheat oven to 425 degrees F. Lightly spray a muffin pan with nonstick spray, or use paper or silicone liners.
Place grated zucchini in a clean kitchen towel and squeeze out excess moisture over a bowl or the sink. Set aside.
In a large bowl, whisk together white whole wheat flour, baking powder, baking soda, salt and cinnamon.
In a medium bowl, whisk together eggs, buttermilk, honey (or maple syrup), vanilla and melted butter.
Pour the wet ingredients into the dry and mix gently with a rubber spatula until almost combined. Gently fold in the zucchini and chocolate chips.
Scoop the batter into the prepared muffin pan.
Bake at 425 degrees for 5 minutes and then reduce oven temperature to 350. Continue baking for 13 to 15 more minutes, or until a tester inserted into the center of a muffin comes out clean. Cool muffins in the pan for 5 minutes before removing to a wire rack to finish cooling.