Capacity is very much related to volume. After a tiring week to find the volume of certain 3D shapes, we finally come to the best part. Converting!! No, no actually it’s really hard to let the students realise that 1 cm³ = 1 ml or 1 dm³ = 1 liter. What do we do? What can we do? This time, we brought all kinds of measuring cups to the class, buckets of water and to make our lessons more interesting, we also brought different types of drink (such as orange juice, mango juice, milk etc). We did lots of activities and at the end of the week, we thought that it’d be great to give them “a treat” (we don’t often do that though). Each one of them could have a glass of juice if they could share equally. How difficult could it be? This is what happened in my class…………..
First of all, they were divided into 2 groups (consist of 8 students). Each table was given some measuring cups, 8 plastic cups and 1 bottle (2 liters) of Berri juice (1 group had orange juice while the other group had mango). They soon found out that in order to be able to share 2 liters of juice equally they needed to convert liters to milliliters then divided by the number of students in each group (2000 milliliters divided by 8 = 250 milliliters). But then they found out that the plastic cups couldn’t hold that much! Oh dear….after a long discussion, they agreed to add 8 more cups in each group and each cup contained 125 milliliters ( 250 : 2 = 125) so each of them could have 2 cups of different juice. Bravo….finally they were heading exactly where I wanted them to go. Oops.. it was too soon for me to celebrate our victory. The 1st group had a little accident when a student knocked out a cup containing 25 milliliters juice. The situation got a bit tense, they started to “argue” while I just stood there watching and wondering whether they could actually resolve their problem. Then someone said “we can’t argue, what is done is done! We need to start all over again since now we can’t pour 125 ml to each cup, let’s get moving!”
I was a bit relieved and went to the other group, who worked quietly and pretty fast. Soon their work was done, but….they could only fill up 15 cups. How come? Another challenge for the 2nd group. First, a student offered not to take his share so it’d be enough for everyone. I had to remain them that this was maths lesson. Giving up his share wouldn’t solve this problem. After a long discussion the agreed to take a closer look, observing cup per cup whether they actually fill the same amount of juice to each cup. They then decided to pour a bit from each cup to fill the last cup. It was done, they filled up 16 cups equally then they began writing reflection on this. This group finished 1st, but what amazed me most was after tidying their table, they went straight to the mat and sit. I could tell that they couldn’t wait to drink their share but instead of that they just sat and waited till the other group finish working so that the whole class could drink at the same time. This activity wasn’t as easy as I thought it’d be, but at the end they sure made my day and brought smile in my face…..