I gathered up a bunch of supplies and experimented to see what would get the grease stains out of the clothes. There were 2 pairs of jeans and 4 t-shirts that had the most grease stains, so I used them for my tests.
I tried baking soda and Oxi Clean, Borax, Dawn, Tide Oxi, Goop, Oxi Clean, Kids 'N Pets, chalk, Dawn Platinum, clarifying shampoo, and Shout Advanced Grease Busting Foam. After each treatment, I washed the clothes in the warm water with Tide Simply Clean. I let each item air dry until I knew if the stain came out. If the stain was still there, I did not put it in the dryer.
Here is what worked and what failed!