Combine yeast and sugar. Pour warm water over the top and let proof for 10 minutes.
Add oil, salt, and two cups of whole wheat flour. Mix in a large stand mixer with your dough hook, or with a regular mixer with as much of the flour as the mixer can handle.
If using a stand mixer, add the rest of the whole wheat flour and then the white flour and knead in the bowl for about 5 minutes. If not, mix in as much flour as your mixer can handle, then take it out of the bowl and knead by hand for 10 minutes.
Place dough in a lightly-greased bowl. Cover with plastic wrap and let rise for about one hour.
Punch dough down and divide into eight pieces.
Roll each half into loaf-shapes.
Place loaves onto two large baking sheets lined with parchment paper or a well greased mini loaf pan.
Cover the eight loaves and allow to rise for about an hour.
Preheat oven to 350 degrees Fahrenheit.
Cook for 25 minutes, or until the top of the loaves are golden brown.