Sift flour, baking powder, baking soda, salt, and cinnamon into mixing bowl and set aside.
In medium bowl, combine shredded carrots and zucchini with sugar. Let sit for 5 minutes.
Add oil and eggs to vegetable and sugar mixture and combine thoroughly.
Add vegetable mixture to dry ingredients and stir until thoroughly combined.
Pour batter into greased and floured pan and bake at 350 F. For two 9 x 1 1/2" round pans, bake 30 - 35 minutes. For one 9 x 12 x 2" cake pan, bake 30 - 35 minutes. For two 1 dozen cupcake pans, bake 18 - 23 minutes. Bake until toothpick inserted near the center comes out clean.
Cool on wire racks for 10 minutes, then remove from pans to cool completely.