by Dave Youngs
The puzzle presented here is not necessarily related to mathematics,
unless there's some "loose tie" to knot theory that I'm "knot"
aware of yet. The puzzle is, however, a powerful one to develop logical thinking.
If your students are able to solve the puzzle, they will not only get the
satisfaction of a job well done, but they will also build their puzzle-solving
confidence. This confidence will help them when tackling future problems.
A Knotty Puzzle challenges each student to tie
a simple overhand knot in a one-meter piece of yarn or string. The catch is
that it must be done by picking up the yarn by its ends and not letting the
ends go until after the knot has been tied.
You need to decide, ahead of time how you want your students
to work on this puzzle. If you introduce the puzzle and have the entire class
work on its simultaneously, when one person solves it others may see this
solution. This will rob them of the experience and satisfaction of solving
the problem themselves. Instead of having the class work on the problem together,
I suggest that you introduce the puzzle at the end of the day and assign it
as homework. This way, the students will be more likely to solve the puzzle
by themselves.
One of the main reasons for doing this type of activity with
students is to help them develop persistence in problem solving. Therefore,
when I assign Puzzle Corner activities to my students, I encouraged them not
to share their solutions with others until the end of the week. At that time,
I set aside part of the math period for students who had solved the puzzle
to share their solutions. During this sharing session, I gave students who
had not yet solved the puzzle, the option of stepping outside for a few minutes
if they didn't want to hear the solution(s).
Student Worksheet
I hope that you enjoy this puzzle.
