Maybe we could do 4 weeks, each getting progressively closer to our subject.
Week 1 - wide as we can go.
Week 2 - something closer, maybe at 35-50mm
Week 3 - closer - telephoto
Week 4 - as close as we can/macro or fill the frame
The last 2 days are free to do as you wish.
The hard part of the challenge would be to select the subjects that would work best with each weeks lens.
Examples
Week 1 - a sunset works in wide
Week 2 - a Celebration works, a parade for example
Week 3 - an instrument would work, you want to see the whole shape and details
Week 4 - Texture works in macro and fill the frame.
What do you think?