Snapshot: 7A Playing Card Proportions

The seventh grade is in the midst of reviewing their understanding of ratios and proportions. They worked with unit rates, did unit conversions in customary and metric units, solved proportions, found percent of change, and applied percents to mark ups and discounts. As we transition into our geometry unit, the class was asked to apply their skills with proportions to make a scale drawing of a playing card. 

Detailed calculations done to scale the playing card.

I like this project because it give the students a sense of how much mathematics is embedded in apps and tools that allow them to proportionally scale images on their devices: click and dragging the corner of an image; pinching or expanding an image on a touch screen; or when a mapping application zooms in or zooms out.


The project allowed for student choice and differentiation. There was a large range of difficulty depending on the card they choose (easy = ace, medium = number cards with increasing difficulty as numbers approached 10, difficult = face card) or the scale factor (easy = 2x, medium = 3.5x, difficult = 1.75x). The project required careful measurement and an understanding of proportional change. 

The students did an outstanding job on the assignment. The scale factor range was 0.5x to 8x. Please stop by the first floor of the sixth street building to check them out in person.