Don't tell anyone, but, it's really day 6. Yesterday was just so ridiculously busy that I didn't do anything that would be considered a challenge.
Today was better.
Prep something: I found 4 boxes of empty canning jars I had gotten from Freecycle and stashed (and forgotten about). They're soaking in hot water. Once they're washed they'll be filled with some prep item (rice, pasta or something) so they can won't take up as much space.
Cook something: Made smoothies with peaches and strawberries from the garden.
Reduce waste: We donated and consigned a huge amount of stuff. I'm liking the empty spaces I'm beginning to see and the fact that I'm getting my prep stuff organized.