In this activity, sixth grade science students learned about the desalination process and peer reviewed each other's work. They were given the task to sketch a design of the process prior to coming into class in order for them to receive constructive criticism by their peers. Their sketches must have included measurements and various labels of the different segments of their design to ultimately show how they contribute to the desalination of salt water into fresh water. Some examples of the student’s drawings are seen below in the slideshow(click the arrows on either side to view different pictures):
The process of desalination of water occurs naturally in what is known as the water cycle. This consists of a few important steps which move water around and change it from a gas to a liquid and back to a gas, even sometimes to ice in between. These steps are precipitation, when the water falls to the ground from the clouds, collection, when the water collects to one place once on the ground, evaporation, when the water changes states and evaporates to the clouds, and condensation, when the water collects and condenses in the clouds and prepares to repeat the cycle.
The students were tasked to recreate the process of desalination which occurs in the evaporation step in the water cycle with ocean trash only. They were provided with some questions to think about while designing their model such as: how can I trap and cool the steam, how can I collect the fresh water, and how does the device work as a whole.
Once they sketched their design, the students took turns peer reviewing each other's work. They used a peer review strategy called “Tag.” In this strategy, the students were encouraged to Tell the designer something they like, Ask the designer a question, and Give the designer a constructive suggestion. Peer reviewing like this is a very important part of science as it helps scientists get validity on their work and ultimately help decide if their work is suitable for publication.