Have each student take the string with an end in each
hand. Have each student tie the string in a knot
wiothout turning loose of either end of the string.
after they try futilely for a few minutes, you show
them a method for tying the string in a knot. You tie
the string in a knot, but you do not show them one step
that you do without them seeing the step. Without that
one step, you cannot tie the knot, but after they try
for a few more minutes, you show them the missing step.
The missing step is that you do have to turn loose of
one end of the string without anyone seeing it. Your
application would be the fact that if you leave out
one step, you cannnot complete the task. After
discussing that concept for a while, you continue by
discussing the ways to describe to someone how to tie
a knot in a string. From there you go to word problems
and begin to look for the proper steps to solve them.