Science in the PYP

Grade 5 have spent the past few weeks investigating the different ways food is produced around the world. After learning about the key characteristics of each mode of production, students shifted their focus to issues of sustainability. Although students had a general idea of what sustainable meant, we pushed our understanding to include what is known as the 3 pillars of sustainability- the economic, social, and environmental impact. The following 2 images were used to help unpack this idea.       

                           

Students were then given 16 characteristics of food production that were previously investigated and asked to place them on a continuum from very sustainable to non-sustainable. Students worked in pairs to share their ideas and build their continuum. A lot of interesting discussions took place around the idea of balancing social justice, economic prosperity and environmental damage. 

We came together as a class to discuss where on the continuum the prompt "Using fertiliser to increase yields" should be placed. Once again, a lively debate ensued with students pointing out the social and economic benefit of increased yields, especially for struggling populations, but at the same time, noting the environmental damage caused by fertiliser. Here are a few students discussing this topic.


This led to the question, 

" Does fertiliser damage the environment?
If so, how"

It was the perfect time to bring science into our inquiry. 

Students were shown the following image and were told the red dots represented Dead Zones. These are places were fish cannot live. We used this as a provocation and a starting point of our investigation. With the help of Se-Eun's explanation, the class looked at the Mississippi river network in the United States and the surrounding farmland. Students noted that applying fertiliser to big farms by crop-dusters, or erosion from rainfall can lead to fertiliser ending up in the river network and eventually draining into the sea. 

The red circles are places that experience Dead Zones-area with low oxygen levels that can't support marine life. As you can see they are in costal regions with dense populations. What causes these Dead Zones? Students will investigate.

An experiment was set up to see what might happen to coastal regions if excessive fertiliser entered the water, and how dead zones form.

For our experiment, 3 beakers were set up per group. One was a control with regular tap water in it, one had lake water, and one had lake water with fertiliser added to it. Each day students will observe the jars and measure the amount of oxygen in the water using a Vernier Dissolved Oxygen Probe.

Unfortunately, the fertilizer we used was blue. I hope we can still see any algae growth that might happen.

Using the probe to measure the amount of oxygen in the water.

Stayed tuned to see the results of this experiment. We think it will take about 2 weeks for the fertiliser to cause an algae bloom, the bloom to die, and the decomposition process to use up all the oxygen in the water.  What was once the lovely water of Senzoku Ike will become a hypoxic dead zone, incapable of supporting marine life. In the meantime, enjoy a nice photo of Senzoku Ike at sundown, before its demise.

       Students grapple with the very real question of how do we feed our growing population, protect the beauty of our planet, and provide a fair, equitable life for all?