Four Coins Investigation

Recently  I spent some time in a primary math class.  We gave the following question adapted from Dr. Marian Small’s Open Question resource.

I have 4 coins.  What might they be?  What are the possibilities?

After the students spent some time coming up with several possibilities we consolidated by asking some different questions:

What is the largest amount possible?

What is the smallest amount?

What amount can you make using 4 different coins?  

 What are some other combinations?

I love high yield, low prep tasks like this because they provide entry points for all students.  This is also an activity that could be easily practised at home.  Some students were able to come up with more examples in the allotted time than others had, but the amount of thinking that went into calculating the different amounts was valuable to observe.  I have learned from past experiences that the students handling the manipulative are usually the ones benefiting the most from the work.  For that reason everyone had their hands on the “money”.

Leave a Reply