|Broken Calculator Challenge – Target 25||Teachers page
and "break" the 1, 8, 5, 2, 0, 3 and - (minus) keys.
List all the different ways you can make 25 on this calculator with keys that are NOT broken. The first one is done for you.
(Only keys that work are: 7, divide, 4, 6, mulitply, open and
close parenthesis, add, equal, and cancel.)
Create more challenges for the students to do!
Try some more Broken Calculator challenges at
Tuesday's lesson - what you can do with a Broken Calculator?
On-math article: Learning Number Sense from a Broken Calculator
Judah Schwartz, George & Judith Collison