Ideas for teaching high school and middle school math. Innovative approaches that address the changing ways that today's student learns material.
 
Picture
When you think of the wonders of the world, you think of Stonehenge, the Colosseum, and the Great Wall. Which are actually all feats of engineering...go STEM! Mr. Franklin called compound interest the Eight Wonder of the world and I do not know I did not hear about this till this past summer after listening to the Podcast "Stuff You Should Know." 

The story goes, a French mathematician basically made fun of Franklin's Poor Richard's Almanack and mocked the American optimism that Franklin exhibited. Franklin, not to be made fun of, accepted the challenge and left 1000 British pounds to both Boston and Philadelphia in 1790 (year of his death.) Both accounts would earn 5% yearly interest and were not the be used till 200 years later (1990).  At the end of the 200 years, the accounts were brought to courts on the legality but at the end Boston received $4.4 million and Philadelphia received $2 million. (Court fees lowed Philly's balance) Wow! 

I had my students read an article about Franklin and the accounts as the start to the class and then we discussed the formula and more examples. It was a neat way to get my students to read math, introduce a topic, and tie in the content to history. I used this lesson in both my Advanced Algebra (Algebra II) and Common Core Coordinate Algebra. I still get comments from my students about it--and its been 2 months since! 

Franklin's story is interesting and makes the math more relatable for students. 

Links to articles:
http://www.crackerjackgreenback.com/the-basics/compound-interest-a-lesson-from-benjamin-franklin/
http://sensuouscurmudgeon.wordpress.com/2008/12/31/ben-franklin-compound-interest-and-evolution/
http://www.globalinvestmentfoundation.org/powerCompInt.html
http://www.upstatenh.com/Finances/BenFranklinsLessonForToday.html

 


Comments

02/07/2013 17:10

Nice story about Franklin. The more I learn about Franklin, Jefferson, and our Founding Fathers, the more impressed I am with what an outstanding group they were!

When it comes to compound interest, I have found students are astounded by experimenting with how more and more frequent compounding approaches a limit, and that the limit is related to e.

Jerry Tuttle
http://onlinecollegemathteacher.blogspot.com/

Reply
Natalie Turbiville
03/20/2013 13:50

I agree! Compound interest is a great topic for ALL students.

Reply

Your comment will be posted after it is approved.


Leave a Reply


Ideas for teaching high school and middle school math. Innovative approaches that address the changing ways that today's student learns material.