TIZITs

TIZIT comes from the phrase, “what is it?,” that is often expressed by viewers when first seeing  images of  these “impossible figures.”

Each TIZIT activity sheet contains labeled dots and instructions for drawing lines between dots to create the shown TIZIT. Download options are for individual pages or groups of pages.

These TIZIT designs were inspired by Escher-type illusions. In the 1980s Mac wrote a Commodore BASIC program which generated any of the 30 different designs available. At each RUN the program scrambled the labels and printed the appropriate directions, but the dot locations didn’t change for a given illusion. Seven designs (shown on the TIZIT Index) with mirrored and rotated variations are available for download as activity sheets, as well as the recently added Tangled TIZITs.

Introduced to his math classes as recreation, these exercises also serve useful purposes as students practice following directions, using a pencil and straight-edge, and thinking about geometrical concepts. Mac strongly discourages free hand sketching of these TIZITs, insisting on quality precision drawings from each student.

The drawings are self-correcting in the sense that it’s usually obvious if a line segment has been misplaced and as lines never cross, students quickly notice if they have made a mistake.

Many students enjoy coloring their completed drawings. The results may be fascinating, depending upon which TIZIT is involved.

Enjoy.

Should you wish to share your TIZIT experiences, Mac would be delighted to hear from you. macoglesby@comcast.net