This Instructional Activity is a part of the Lesson 2, Unit 7, Grade 8. As an option, the discussion can be framed as a challenge. Distribute compasses, and ask students, "How can we determine an estimate for the length of the diagonal of the unit square?" Consider a unit square, a square with side lengths equal to 1. How can we determine the length of the diagonal, s, of the unit square? We can use the Pythagorean theorem to determine the length of the diagonal.