I make these all the time for my kids and even take them for snack at preschool:
http://www.healthy-diet-mom.com/healthy-pumpkin-muffins.html
I use all whole wheat flour and cut the sugar back to 1/2c. I also never put on the topping--these are breakfast for the kids and they don't need the extra sugar. I want to experiment with using honey or maple syrup instead of sugar. You could search on how to replace the sugar with bananas or applesauce. If I make the recipe with mini muffins, I can get about 32 muffins out of it. Super healthy recipe that actually tastes great and is relatively low in sugar!