"Kajitsu" is Japanese for "a morsel of fruit". Cutting the fruit into bite sized morsels requires students to practice mirror & rotational symmetry. Top students are engaged in the tough problem solving while the rest of the class learns and practices symmetry.
Of all MathPickle puzzle designs, this is the most physically beautiful. I often have students ask for a spare puzzle-sheet just so they can redraw their answers beautifully - so this puzzle's look helps inspire aesthetically minded students who might otherwise be uninspired.
45 minutes is what I've listed, but there is enough material here for a few weeks if so desired.
This pdf file includes written rules, but also a link to 6 minute video rules. Both are easy ;-)
Standards for Mathematical Practice:
All MathPickle puzzle designs, including Kajitsu, are guaranteed to engage a wide spectrum of student abilities while targeting the following Standards for Mathematical Practice:
MP1 Toughen up!
This is problem solving where our students develop grit and resiliency in the face of nasty, thorny problems. It is the most sought after skill for our students.
MP3 Work together!
This is collaborative problem solving in which students discuss their strategies to solve a problem and identify missteps in a failed solution. MathPickle recommends pairing up students for all its puzzles.
MP6 Be precise!
This is where our students learn to communicate using precise terminology. MathPickle encourages students not only to use the precise terms of others, but to invent and rigorously define their own terms.
MP7 Be observant!
One of the things that the human brain does very well is identify pattern. We sometimes do this too well and identify patterns that don't really exist.
Common Core State Standards for grades 4 & 8:
Recognize a line of symmetry for a two-dimensional figure as a line across the figure such that the figure can be folded along the line into matching parts. Identify line-symmetric figures and draw lines of symmetry.
Verify experimentally the properties of rotations, reflections, and translations:
Lines are taken to lines, and line segments to line segments of the same length.
Angles are taken to angles of the same measure.
Parallel lines are taken to parallel lines.