The idea was probably Mondrian inspired, mixed with a geometry activity that I like: divide a geoboard into four non-congruent equal parts.
The task for this one is to make different fractions that add, or fit together, to one, or a whole square. Had very interesting conversation with Dave Coffey today about fractions and introducing operations, and representation... and then that conversation spread to Lisa Kasmer. Nice to work with such interesting colleagues.
EDIT: oops! had the permission set incorrectly on this. If it's not appearing below, here's the link to the pdf.
Two examples from my preservice teachers. The second one was made with flaps that lifted up to reveal the value of the fraction shown. Nice!
You can have your students simplify or not - both create interesting situations.
A nice extension challenge is to do this Egyptian style, with all unit fractions.