Bananas and Science!

Nothing excites me more than to watch my students discover learning while exploring the world around them!  One of my favorite fruits to eat is the banana!  I posed the question, I wonder, what percentage of a banana is edible?  We began the activity with an anticipation guide!  This consisted of four true and false questions.

1.  The banana is a berry?
2.  Bananas grow on trees?
3.  Pound for pound, bananas are the most widely sold fruit in the United States.
4.  Bananas are highly nutritious and easily digestible.

These questions made for a very friendly and respectful debate. Next, each group of three - four students received a passage on the banana.  Students then participated in "Reciprocal Teaching" to gather information about bananas.  Groups then organized their thinking in a thinking map to share with the class.  Students then "revised" their knowledge regarding the banana.

The next day, I posed the same question, "I wonder how much of the banana is edible".  Each group of two received a banana, balance scale, and "gram stackers".  First students estimated the percentage of the banana that is edible.  Several students said 50%. Students then discussed with their partner how they think they will find this information.  Students worked together and came up with a plan to find the percentage of the banana that is edible.  Their plan MATCHED mine!  Students first found the mass of the entire banana by placing it in the cup on one side of balance scale and gram stackers in the other cup on the other side of the balance scale.  Once the scale was balanced, students counted the gram stackers to calculate the mass of the entire banana.

Students then peeled the banana and found the mass of the peel and the "meat" of the banana.  Students recorded the data on a data sheet.  At this point we spoke about accuracy in our measurements.  

I demonstrated that if we take the mass of the peel and the mass of the "meat", it should equal the mass of the entire banana!  Some groups were exact while some were not.  We then discussed why some of the measurements were not exact.  

Next we found the percentage of the banana that is edible by taking the mass of the edible part of the banana and divided it by the total mass of the banana!  

This led to a conversation about purchasing bananas.  I posed the question, is it better to buy bananas that are a little green and not yet ripe (where the peel is thicker) or should we wait until the bananas are a bit more ripe?  Most of my nine and ten year olds figured out that if we purchase bananas that are not quite ripe, we would be wasting money because the percentage of the edible portion is lower!  

Now, I wish I could say this activity is all my idea, but I can't!  This activity comes from Aimes Education Foundation.  Here is a link to the activity!  Hope you can use this in your classroom!