Challenge 23 is draw your foot, so here's mine, including my almost non-existent pinkie toenail.
Challenge 71 is to draw something representing my favorite sport. I picked tennis, even though I do not play nearly as much anymore. But tennis is one of those sports where you have fun and get fit without noticing. All that running, shifting, aiming, hitting, darting back and forth, anticipating--it's such good exercise.
I did this in 2B pencil, and I did get tired of doing the strings, so that's why it looks like a giraffe skin in the middle! My racket is strung better than I have drawn it.