Macy’s Star Rewards Points

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Wow! Check out this deal at Macy’s.  For $25 I can join Macy’s Star Rewards program.  I get 10% back in rewards for every dollar I spend.  Its pretty cool that Macy’s gives part of that $25 to charity.  Should you do it?  It seems like free money (or clothes) just for shopping at Macy’s.  Factoring in the $25 enrollment fee, how much do you need to spend at Macy’s to come out ahead? For what total shopping dollar amounts is this a bad deal for the consumer?  What dollar amount must you spend to at least break even?  Can you write a rule that gives the dollars earned at Macy’s after the $25 registration fee for any dollar amount of purchases?

How large a TV should I get?

This is a great looking room, but do you see what is wrong with this picture?
small HDTV 2

Clicking on this image will show it larger.

Whether you are in middle school or high school, someday you are going to be moving out and you might need to select the right size HDTV for your living space.  I found this guide that helps buyers pick the correct size HDTV for a living space.  Take a look at the table.  What questions do you have?  What do you notice?


Clicking on this image will show it larger.

In this activity students will select the appropriate size HDTV for various rooms.  They will need to read and use a scale, make measurements, possibly place furnishings and then correctly determine the right size and placement of the HDTV.

Students may also need to determine how long an HDTV is based off it size (HDTV size is determined by the diagonal screen length) if you choose to have them accurately sketch it into the room.

Thinking about Columbus

nina-picThe Niña

Can you imagine sailing off to the West, into empty looking ocean, to find what your captain believes is a good route to the Indian subcontinent?  This was a pretty risky navigational feat.  Luckily the ships experienced good weather on their trip to the Caribbean.

Use some of what we know now about navigation to examine this trek and do some reasoning and experimentation with the data.

MAVEN arrives at Mars

Recently the MAVEN spacecraft (Mars Atmosphere and Volatile Evolution Mission) that was launched on November  18, 2013 reached Mars and attained an elongated orbit around the planet.  How does someone figure out how to do that?

Steepness and Fall hiking

 Mt. Washington, NH

Fall is a beautiful time of year for hiking. Many students will be walking in the woods and mountains to enjoy the colorful leaves and the cool weather outside.  Let them combine what they are doing with their families and friends with a little mathematics about percent grade change.  Why are there warnings about a 6% road grade change ahead?  Why does everyone talk about the vertical gain on a trail that is only 3 miles long?  Enjoy using slope and the Pythagorean Theorem in a new way.

iPhone 6 opening weekend


long wait for iPhone 6


Headline of NYTimes technology section on September 22, 2014

Apple’s latest iPhone, the iPhone 6, is out.  The opening weekend was full of long lines, waits and sold out stores.  With all of this hoopla, could the iPhone 6 outsell the 9 million iPhone 5s/5c’s that were sold during their opening weekend in 2013?  In this activity kids explore past iPhone launch sales data and predict how many iPhone 6’s were sold during the opening weekend in 2014.  Younger students can investigate the data through a bar graph, while older students can use a scatter plot and even use equations to model sales growth.  Technology: Students can model the data with linear, quadratic or exponential models at this interactive Desmos graphing activity, the data and sliders are all set to go.  Let your students rough out their models & predictions as they work through the activity.