Wednesday, November 11, 2015

Glowing rectangles

People spend lots of time staring at their screens (glowing rectangles).  Kids spend hours each day using their cell phones, computers, tablets, television and more.  Use that interest to motivate your student’s analysis of screen ratios and what proportions they are looking at.

Not all screens have the same proportions.  Some televisions are tube televisions and they look more like squares compared to HDTVs.  Did you ever notice that movies and movie theaters use screen dimensions called wide screen?  Where do the iPad, iPhone, and other smart phone and tablet screen dimensions fall?

Use this investigation to discover and work with the proportions of all of these glowing rectangles.  Students will use ratio tables and grapple with open ended questions as they develop mathematical ideas about ratio and proportionality.  Consider sharing the image at the bottom of this post, which gives a view of various aspect ratios.  Consider starting the activity with the picture of the two television sets pictured here.  Let kids look at the picture and take some questions or noticing that they might have.  Share this hilarious Onion article on “glowing rectangles” and then get the activity going.  Let kids work with partners or groups, see how far they can get on their own, before you need to bring the class together from some discussion on similar figures.  Students should have a little experience with ratio tables and proportionality if they are going to try this activity without some direct instruction.  Or use the activity as review and application of proportionality and similar figures.

glowing-rectangles2015.pdf

CCSS: 6.RP.1, 6.RP.2, 6. RP.3, 7.RP.1, 7.RP.2, 7.G.1

For members we have solutions and tips.

from Yummy Math http://www.yummymath.com/2015/glowing-rectangles-2/