Why do this problem?
requires learners to look closely at a design, and see how it can be divided into squares, and built up from simple pieces. It will involve mathematical language, using words such as 'curved' and 'straight', 'vertical', 'horizontal' and 'diagonal'. It should encourage useful discussion between those working together.
You could start by showing the group the problem as it is given, show a bit of the interactivity and then challenge them to continue.
Alternatively, you could show them this snippet from YouTube
as a start. [You may prefer to show this faster version
from YouTube.] Then show the group the simplified knot used in this problem and then go on from there.
Learners can then continue in pairs either using the interactivity or these cards. Four copies of the first sheet will be needed to make a complete set of the cards. The design is more easily and satisfactorily built up on a $24$ cm square divided into a six by six grid. This
will just fit on a sheet of A3 paper. There is also a second page of the download with two copies of the design itself.
At the end of the session bring the group together again and discuss their findings. Ask what they found easiest to do and most difficult in building up the knot. How many different strands are there in this particular Celtic knot? If they have not already seen it, the piece from YouTube
might make an interesting ending to the
Some learners may like to read about Celtic knots. This article
or this in Wikipedia
may be found useful and interesting.
Which pieces do you think go where?
Are you remembering that the line turns at the edges?
What do you notice about the way that the lines pass each other?
Learners could be challenged to make an $8$ by $8$ Celtic Knot on squared paper. Or, alternatively, attempt some of the designs shown in this article
. Some may also like to try Drawing Celtic Knots
Suggest finding the four corner pieces and putting them in place. The pieces with curves then go next. Follow the design from this sheet