How Many Pennies did Otha Save?

Otha Anders used picking up pennies as a way to remember to pray.  In this 3-act activity we try to estimate how much he actually collected and stored in 5 gallon water jugs. This activity address modeling with math, estimating, and can serve as a great way for students to reason, problem solve and communicate mathematical thinking while practicing division and multiplication with decimals.

Option 1:

Kick off the activity with the article with vital information grayed out (number of pennies, value and number of jugs). Read the article together as a class. Ask kids how many pennies they think Otha saved over 45 years.

You might see students estimate the number of pennies saved on average per day or per week and then consider how many days or weeks have gone by in 45 years.  Students might have many different ways to reason through the problem, so let them go with their intuitive reasoning.  

Option 2:

You could also start the activity by sharing the number of five gallon jugs Otha had filled by sharing this version: article with number of jugs showing but the other information grayed out.  Or give this info after kids have estimated the number of pennies he saved over 45 years using their own intuitive strategies. There is a video about this story here but be careful, the answer is given in the headline of the story below the video. 

This activity could span a number of grade levels. Kids are estimating, reasoning and working with rational numbers.  Finally, this is a great activity for high school students to engage in modeling and practice basic operations with rational numbers.  It is also very likely that students will engage in the following math practices: MP1, MP2, MP3 and MP4.

Special thanks to Sheri Flecca telling us about this news story and suggesting it as a possible activity.