Marshmallow Estimation

It is rare for my daughter to have hot cocoa with her breakfast.  This morning, she prepared a cup of hot cocoa to eat with her French toast.  As she added the marshmallows to the cocoa, she asked if we could make Rice Krispie Treats later. Why not, it's winter break I thought.

This afternoon we came back to the kitchen to make the treats.  Yikes!  I found one opened package of marshmallows and tossed through the pantry to find more. I could not find any in the pantry and I feared that she had nibbled too many this morning.  Do we have enough to make the recipe that calls for 4 cups of mini marshmallows?  I asked my daughter to do some estimation.  She estimated that we did.  How can we find out if we are correct? She told me to grab the measuring cup to prove it.  Perfect estimate!  We had just enough.  Yum! Yum!

Asking her to use estimation, then actually filling up the measuring cup (before we continued with the recipe), reminded me of the water tank problem in the powerful TED Talk by Dan Meyer.  He does an amazing job of explaining how Math Class Needs a Makeover and how we use math to make sense of our world.  Listen for the water tank example...

As Mr. Meyer suggested in the video, I used authentic materials and visuals (which are a step better for her than photos and videos).  I involved my daughter in the formulation of an authentic problem to solve that had real-life benefits.  We did not check the answer key or back of the book for the answer to our estimation question.  We used our measuring cup to figure out the answer.

I think we, as teachers, need to start seeing how math makes sense in our personal world so that we can bring more authentic experiences to the classroom.  I will continue looking and noticing these connections! Stay tuned...

As I just looked at her 3rd grade Common Core State Standards, I realized I could have made our spontaneous math experience more standards-based.  (Since I coach K-5th grade, I do not always have immediate recall of each grade level's standards.)  I asked her to estimate if we had enough cups instead of the suggested measures (below). I guess that means we will have to convert measurements and try the recipe again another day!  No problem!

CCSS.Math.Content.3.MD.A.2
Measure and estimate liquid volumes and masses of objects using standard units of grams (g), kilograms (kg), and liters (l).