This is a fun way to start introducing the concept of Pi (as a precursor to circle measurement)
There is a huge internet movement going on that finally makes it cool to be a nerd and the students respond really well to this. Get them excited to become part of the math culture devoted to Pi.
This challenge asks them face off against each other in a Pi digit challenge. Students absolutely love the opportunity to be up and competing. At the end of the day, even if a student loses every challenge, he/she will still come out with an above average knowledge of Pi, which they will love.
The activity is explained explicitly through instructional slides, with a teacher guide included at the end.
I do not assess this challenge- this is meant to be purely a motivational activity and it does wonders for your circle measurement unit.