Evaporation and the water cycle
For This assignment I will be focussing on the water cycle. Water is the basis of life on earth, without it living creatures cannot survive for long. Water is vital for living cells and for many of the processes the body carries out on a daily basis. The human body is made up of between 55-75% water. Put another way each and every person is made up of between half and three-quarters water! We need to drink lots of water regularly because when we breathe, sweat and urinate some of that water we store leaves our body so we need to replace it by drinking water. The best thing for us is to drink plain water because cordials and soft drinks have lots of sugar that is bad for teeth. Due to the drought over the years in Australia, water has become an increasingly scarce and precious resource.
To help the children understand the water cycle I will play them a song that I found on You Tube called “The Water Cycle Song”. This song was sung by a group of primary school children in America. The song explains the water cycle in detail but is a fun and interactive way of ending a lesson and reinforcing the terms and processes covered in the rest of the lesson. The video clip which accompanies the song shows diagrams of the processes which are described through the song.
http://www.youtube.com/watch?v=maxLwmDxoVI&feature=related
“ Did a Dinosaur Drink This Water?”: http://books.google.com.au/books?id=gx02NgAACAAJ&dq=did+a+dinosaur+drink+this+water%3F&cd=1.) .) This book is full of beautiful and interesting illustrations which will appeal to young children and help visual learners to understand the message. People whose learning preference is reading text will also find this book very instructive and auditory learners will find the language maintains their interest as I read sections out loud.
“The Drop in my Drink”: http://books.google.com.au/books?id=2SBIVHdmD5IC&printsec=frontcover&dq=the+drop+in+my+drink&cd=1#v=onepage&q=&f=false This book is aimed at an older age group than the story ‘Did a Dinosaur Drink This Water?’ but I have selected it because it has very good photographs illustrating the behaviour of water in different situations. This book was written by Meredith Hooper and Chris Coady.
Common Misconceptions
When learning about the water cycle, expect to hear many various misconceptions about the water cycle that must be corrected. Some examples are:
-That Clouds are made of smoke, pillows, cotton or wool.
-Clouds are supernatural events (God, or Angels)
-Water is absorbed into surfaces, rather than evaporated into air
-When water evaporates it disappears or ceases to exist.
-The Sun and Clouds combine to make it rain.
-Water come from a tap then you drink it or it disappears down the drain.
Misconceptions are formed from children observing what’s happening around them. Seeing things like a tap and watching the water go down the drain, a child may start thinking that the tap creates water, as they may not know about plumbing. Also, children may think that clouds are like people, in that they sweat, and the rain is clouds sweating from moving around so much, or being shaken like a sponge.
The best way to change their ideas on the water cycle is not to tell them they’re wrong while telling them the correct answer, but to show it to them and see what they make of it, using activity II. Allow the students to investigate the water cycle for themselves, and link it with their lives and interests. The teacher must also explain the science idea, the language and resources used and how it can be applied in the student’s lives (Sharp, K. 1998).
One way of reinforcing the water cycle would be to have the stages of the water cycled displayed in the classroom. The teacher could go through them with the children, showing them what each one is and putting them in order on a wall for them to see.
Rich Task
Class activity: Drawing about the water cycle
Begin the class with a brief run through of what they have already learned about the water cycle and its concepts from a previous class.
Using pictures and examples explain the water cycle as a visual cue can assist the students with remembering what they have been taught.
Provide the students with some paper and drawing materials ask them to draw what they know about the steps of the water cycle and write down/ label what they can, also ask the students to write anything else they have learned or know about the water cycle and water in general (e.g. floods, storms, cloud etc. (An option to assist the students is to ask them to talk with a partner about the first step) Send the class off to draw and write what they know.
Assessment criteria: The students need to be able to show and label what they know about the water cycle from learning in previous classes. I will expect to see pictures such as the one below but in their own way with labels, depending on their level of understanding I expect to see detail and particular words such as condensation, precipitation, evaporation, I expect to see in their drawings rivers, lakes, the sun and clouds. Their drawing should show the cycle in order using arrows or line. Some children may like to explain their understandings with sentences. They can be creative with colour.
Indicators of student’s deep understanding of science concepts
The students are able to draw with detail to show their understanding of the water cycle. They can also show understanding of other concepts in relation to the water cycle such as drought, floods, how water is affecting people’s lives, farms, water restrictions etc
This is an example of a basic understanding with no labelling or other explanations.
References:
ACT Department of Education and Training.(2007) Every Chance to Learn. Canberra, Australia. Accessed online 12 may 2010
Australian Curriculum Assessment and Reporting Authority. (2010). Draft K-10 Australian curriculum in English, history, science and mathematics. Commonwealth of Australia. Canberra, Australia.
Krause, K.L., Bochner, S.& Duchesne, S. (2003) Educational psychology for learning and teaching (3rd ed.) Melbourne, Australia: Cengage Learning.
New South Wales Board of Studies. (2005) NSW primary curriculum. Foundation statements / Board of Studies New South Wales. Accessed online 12 may 2010.
Wetzel, D. R (2008) Children's Science Misconceptions about Weather, Suite 101 http://homeschooling.suite101.com/article.cfm/childrens_science_misconceptions
http://mbgnet.mobot.org/fresh/cycle/index.htm.
http://mbgnet.mobot.org/fresh/cycle/concepts.htm.
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http://members.optusnet.com.au/benjamink/Water/TheWaterCycleWebQuest.htm |
http://www.huntel.net/rsweetland/science/misconceptions/weather.html
Experiment 1
The first experiment I would ask the children to conduct would involve putting 4 ice cubes in a glass. Water (at room temperature) will then be added until the glass is filled to the top. I would then ask the children to observe any changes that occur while watching the water level of the glass and the size of the ice cubes.
I chose to base my lessons on experiments because educational theory tells us that children learn more effectively through hands on experimentation, this is in line with Piaget’s theory of stages of development (Krause et al, 2003)
As a class I would then get the children to report back to me with their observations which would be recorded on the white/smart board.
Experiment 2
Experiment two shows children the evaporation process. I would ask one of my students to place two heatproof glasses on the demonstration table. I would then fill each cup with equal amounts of water, which I would ask one of my students to measure out for me. I would then ask another student to confirm that both cups have equal amounts of water in them. One of the water filled glasses would then remain on the demonstration table and the other would be placed in a fridge.
We would then pour the glass of water on the table into an open electric saucepan and switch the electricity on. While the water was heating I would have a conversation with my class about the water cycle and some of the scientific terms that are used to explain the process of the water cycle, including evaporation, precipitation and condensation. I would then add these terms and their meanings to the class word wall for future reference.
Once the water had boiled for a while I would pour it back into the empty glass. I would then ask a student to retrieve the glass from the fridge and place it next to the glass on the table and ask the students to tell me if they notice any differences. (Heat is one of the methods that speeds up the evaporation process so the glass that contains the boiled water will have less water in it than the water that was placed in the fridge.)
Teaching notes for Experiment 1 & 2
Each group will have a manager to collect materials (drinking glass, water and ice cubes, a team spokesperson (in charge of communicating with the teacher and class on behalf of the group) and a team motivator (in charge of keeping the team on track and motivated). Roles within the group will be rotated around daily.
Allocating defined roles to children in the class is a teaching technique that I have picked up in the science tutorials. Having allocated rules helps the lesson to run smoothly. Having a manager to get the materials means that you have 4 or 5 children gathered around getting materials rather than 24 and the same theory applies to the spokesperson for the group there are only 4 or 5 children approaching the teacher seeking advice rather than 24 which means the teacher can provide more help to the students because they aren’t concentrating on children with personal space issues which includes hitting and pushing.
Activity 3
Rain Activity
Ages: 3-5
Materials: Cotton wool, pan and glasses of water.
This activity will help the kids get a hands on approach to how and why clouds rain.
Teaching notes: Teach must make sure that they revisit prior learning regarding the water cycle. Teachers must make sure they use the technical terms such as condensation, precipitation etc as long as they make sure the students are clear about what each of these terms mean.
Step 1: Each child gets a pan or plate (something to catch the water) and a glass of water and some cotton balls.
Step 2: Explain to the children that the cotton wool represents a cloud.
I would ask the students what does the cloud feel like, what would a real cloud feeli like and what do clouds do.
Step 3: The children dip the cotton ball into the glass and let it soak up some water.
I would begin to ask the students why the clouds are soaking up water and can we see whether real clouds are full of water or not. To help reinforce what clouds do i would ask the students whether the cloud is heavier or lighter than before and why is it heavier.
-Step 4: Each child lifts up their cotton ball and watches it leak water.
Here i would ask why the cloud is leaking water? Wjhat does this represent? How did it rain and what happened to the cloud after all the water had rained out.
Step 5: After the cloud had no more water in it i would begin to ask the students where would the rain go? Why is this important and bring the activity back intot heir worlds by getting them to understand why we need water catchment areas etc.\
Optional:
I could even get a fan and turn it on before the children lift up their cotton clouds and ask the students why the droplets are flying everywhere.