Science Around Us – Clouds 1 – Why Are Clouds White
A group of small clouds passing by
Clouds are made up from millions of tiny water droplets that float in the air. The sunlight that shines onto them is a mixture of the rainbow colours which makes the light white. This white light shines onto the droplets and they behave like millions of tiny mirrors reflecting the white light in all directions. The reflection of the light makes the clouds appear white.
Pippa gathered some equipment and materials to make a model cloud.
Pippa in her kitchen lab
She poured some olive oil into the water. In this model the water represents the air and the oil represents the material (the water droplets) in the cloud.
The oil and water ready to be mixed
Pippa stirred up the oil and water. As oil and water do not mix, the oil began to form tiny droplets in the water.
Pippa stirred up the oil and wate
As Pippa stirred the droplets became smaller and smaller until they behaved like the water droplets in a cloud and reflected the white light in the kitchen in all directions.
Pippa’s model cloud
How do clouds stay up in the air?
The billions of water droplets that make up a cloud are smaller in diameter than a hair on your arm. If you could scoop up part of the cloud shown in the first picture and put it in a box measuring one metre square (or about the size of a kitchen fridge) and measure the weight of all the water droplets in it you would find they weighed about as much as one baked bean. This means they weigh very, very little and any upward movement in the air (such as wind or rising air from the warm ground) will keep them in the air.
Next topic – Clouds 2 – How are clouds made?
Science Around Us – Why Is The Sky Blue
Children often ask questions which need a scientific explanation. The memory of the explanations can be extended when an activity is featured. In this series of blogs I have put together some questions that children ask and offered simple explanations which are illustrated by activities that my youngest granddaughter Pippa carried out.
I also include links to other sites to provide further information and details of how to carry out practical work with your children if you wish.
I hope the series will be useful to parents, grandparents and carers for talking about science after school or in the holidays and maybe teachers may find something of interest too.
I am beginning with a series of topics related to the closest thing to us – the air and atmosphere.
Science Around Us 1. Sky colours
Why is the sky blue?
Blue sky above a magnolia tree in Lancashire.
Warning Never look at the Sun in the sky it can damage your eyes!
The colours in the sky come from the rays of light that reach us from the Sun. Sunlight is made up from light of different colours – the colours of the rainbow. Light travels in the form of waves (called electromagnetic waves) and each colour has wave crests that have a certain distance between them. This distance is called the wavelength. Blue light has short wave lengths and red and yellow light have longer wave lengths.
When you look up into the sky you are looking up into the atmosphere. It is made up of molecules of gases, mainly nitrogen and oxygen. As the sunlight shines through the atmosphere the waves of light are scattered and reflected by the molecules of gas. The short waves of the blue light are scattered and reflected the most and this makes the sky blue.
Making a model sky
Pippa has collected items to make a model of the blue sky.
There is an empty olive oil bottle, a torch, a jug of water, a small churn of milk and a teaspoon. The milk will take the part of the molecules of oxygen and nitrogen. Before she uses the milk she makes sure she makes a fair test. This test will show that is the milk the makes the blue light and not the water.
First she fills the bottle with water, places it on its side and shines the torch into the bottle
Shining the torch through water in the bottle.
Next she adds about a third of a teaspoonful of milk to the bottle and shakes it up then shines her torch again.
Shining the torch into the model sky
Why is the sky less blue near the horizon?
A clear sky over the Yorkshire Dales.
In this picture you can see that the sky has become whiter as you look towards the horizon (the place where the Earth meets the sky).
This change is due to the Sun sinking lower in the sky (It is on the left of this picture) and as it does so its light rays pass through a thicker layer of the air. See the picture here.
As the light passes through more air it is more greatly scattered and the different colours of light mix up to make a whitish light.
What makes a sky red?
Red skies can occur in the direction of the Sun at sunrise and sunset. Again it is partially due to the extra thickness of the air that the light passes through but is mainly caused by dust particles and even salt crystals blown up from the surface of the sea. They scatter the blue light completely,but red light is scattered less so making the sky appear red.
Sunrise at Robin Hood’s Bay, Yorkshire
Remember the warning – Never look at the Sun it can damage your eyes.
Here is an experiment to show you how to make a model red sunset.
Next Topic – Why are clouds white?
Mini beasts – a beautiful science activity?
In recent blogs I have been considering the science people remember from their school days and also suggesting that science does not need to be perceived as hard but can be beautiful. In the blog on beauty I used a simple description of beauty as something which can generate pleasure and satisfaction.
I saw this in action when I visited my local primary school to help with their study of mini beasts.
The lesson began by looking at the film What animal is it? which is free to view at http://www.peterdriley.com/books/ways-into-science-series/
This sets mini beasts in context in the animal kingdom.
The children then explored the school grounds to make a mini beast survey. In the survey the mini beasts were identified and counted.
Identifying and counting the minibeasts
After twenty minutes the children returned to the classroom and discussed the data they had collected.
I pointed out that they had made their survey during the day and asked them how they could find out about the mini beasts that might be active at night?
Followers of Spring Watch suggested setting up cameras but others suggested a much cheaper alternative of setting up traps and I showed them how to make a pit fall trap.
The pit fall trap
These were set up all over the school grounds.
Creating pitfall traps
The following morning the traps were emptied and the mini beasts were identified and counted and added to the data collected the previous day.
The children then wrote up their investigation using the free downloadable Experiment Report sheets from my website at http://www.peterdriley.com/downloads-and-resources/ (scroll down to The Experiment Report sheet and receive it in a zip file).
An experiment report sheet
An experiment report sheet
They completed their mini beast study by using https://nces.ed.gov/nceskids/graphing/classic/ to make bar graphs and pie charts.
Mini beast bar chart
Mini beast bar chart
You can see by their reports and graphs that the children had found the science activity pleasant and it gave them satisfaction to spend time writing it up and making the graphs and charts. Perhaps science is beautiful after all.
The school has agreed for their work to be displayed in the Science Exhibition Gallery at
http://www.peterdriley.com/category/science-exhibition-gallery/
If you and your children have done a science activity that is an example of the beauty of science like this one please send it in to peter@peterdriley.com for display in the Science Exhibition Gallery for every one to see.
Using the books and films together
In my last blog I talked about visual aids that I had used as a teacher many years ago and how I was bringing them up to date with films with notes.
In fact, the films I have made are to go with my books in the Ways into Science series and the notes, called Stop and Chat, are to extend your children’s interaction with the topic and with you.
Find out more about them at http://www.peterdriley.com/books/ways-into-science-series/
To use the book, film and resources simply follow these few steps.
1. Download the zip file and print off the Stop and Chat sheet. (The zip file also contains a quiz, answer sheet and experiment report sheet that you might like to use with the book).
2. Sit at the computer with your child with their book, and your Stop and Chat sheet and click on the film.
3. You may like to run through the film with your child without the Stop and Chat sheet so both of you can see how the topic is presented.
4. Play the film again but this time stop it at the times shown on the sheet and use the notes to ask your child about the topic or perform an activity. The stop and chat sheet has times at which you should stop the film and just … chat. Try it.
5. You may find that the notes suggest activities which you can do with your children and they can write them up on the report sheet downloaded from the zip file to keep a record of their developing science knowledge in a science file.
Please have a go and let me know how you got on by writing to peter@peterdriley.com
Visual Aids Then and Now
When I began teaching over forty-five years ago visual aids for science were in their infancy. Some of the laboratories I did my teaching practice in had posters on the walls that were tinged with yellow and brown and had probably been in use for another forty years before!
Here is a link to some of the kinds of posters I used when I began teaching. Older readers may also remember them.
It wasn’t long after, as we moved into the seventies, that educational suppliers began producing more colourful and lively ones – a tradition that continues to the present day. Here is an example produced by Chris, the illustrator of the website, for my series of scientific method posters.
You may download them all free at
http://www.peterdriley.com/downloads-and-resources/
Back in the day biological specimens were contained in glass jars filled with formalin. In one laboratory I taught in there was a python’s head staring out from a jar on a shelf by the chalkboard. Today these pickled specimens are replaced by plastic models such as this one.
A plastic torso
In those early days, without computers and powerpoint presentations, the department was equipped with a slide projector and screen. Educational suppliers were producing slides on themes such a plants or invertebrates and providing notes that you could read out. I found them very useful. Here is a sample of two slides and notes I have prepared to show you how it worked. You might like to look at the picture and read out the notes as I used to do, to get the idea of how the slide show was presented.
Grass plant
Notes – Grass plants have wind pollinated flowers. When the flowers are ready to release their pollen, structures called stamens hang out of the flowers. On the end of each stamen is a swelling called an anther in which the pollen grains are made. These anthers open and release the pollen into the air.
Flower
Notes – Plants that use insects for pollination produce flowers with brightly coloured petals, which also produce a scent. At the base of the petals are structures called nectaries. They make nectar, a sugary liquid, which insects use for food. The petals may have lines on them called honey guides which direct the insect to the centre of the flower where the nectaries are. As the insects make their journey they brush against the stamens in the centre of the flower and pick up pollen from the anthers.
I used many of these slide sets then began making my own collection of slides and writing my own notes then recording them onto a cassette recorder (remember them?). These slide sets and cassettes became widely used in the department when biology was being taught.
A couple of years ago I looked back on those days and decided to bring the whole process up to date with short films and teaching notes. You can see one of them on the home page of my website.
Ways Into Science – Seasons
Click on the film and have a look.
Click on the link to the Stop and Chat to see my teaching notes.
In the next blog I will explain how the films and Stop and Chat notes can be used together either at home or in class to stimulate discussion and science activities with your children.
Just to return to the slide shows of the past. At the moment I am working on a project with one of my granddaughters, bringing this process up to date with a short powerpoint presentation about the nature around her home. I hope to post this as a blog nearer the end of summer.
Perhaps you might like to make one with your children or grandchildren or class and send it in for the science exhibition gallery to peter@peterdriley.com
Owen’s bean stalk keeps on growing
Back in March a reception class visited the Playbarn where we looked at life on a farm and everyone took home a bean seed to grow. Here is one that has been making progress.
On 20th April it was 69 cm tall.
Beanstalk
On the 9th of June it had reached 1 meter 50 cms. It has had flowers and is now growing pods There are plans to plant it outside so the pods can ripen and the new beans collected to show the life cycle of a plant.
Beanstalk
Owl Pellet Dissection
One of my granddaughters, Tabitha, has read every Harry Potter book at least three times and thinks owls are the best birds ever! Her class have been studying animals in their habitats so I thought we could enrich their work on food chains with owl pellet dissections.
My granddaughter and myself
I obtained the owl pellets from the Suffolk Owl Sanctuary who also provide advice on dissection and identification charts.
What is an owl pellet?
When an owl catches its food, such as a mouse, it swallows its food whole. In the digestive system the fleshy parts of the food are broken down and absorbed into the body but the less digestible material – bones and fur – are not. They are wrapped up into a pellet and released through the body back through the mouth and beak.
How are owl pellets useful in the curriculum?
They are particularly useful in work on food chains as they can show what the owl has been eating.
How is the dissection made?
The children used eye brow tweezers and cocktail sticks to separate the items in the pellets.
The children used tweezers and cocktail sticks to separate the items
Separating the contents
Pellet contents
The children used the identification charts to find out what the owls had been eating
They placed the bones on the pictures to find a match
What did the owl pellets contain?
Evidence from the pellets showed that most of the owls had been feeding on mice but one had eaten a shrew. This was confirmed when the lower jaw bones of the shrew were found with its red capped, crocodile- like teeth!
The beanstalks keep on growing
Continuing on from my previous post about children at Settle school planting beanstalks, more reports on their progress have been coming in to the school. They show just how enthusiastic the children have been about taking care of their beanstalks and they have used several different ways to measure the growth of them…
How to make a rain gauge for measuring rainfall
In my last post I described visiting Towneley hall and seeing Richard Towneley’s rain gauge which was built in the 1670s. Today we’ll be looking at building our own rain gauge…
Primary Science : Teaching the scientific method by growing beans
The nursery and reception classes at Settle School have been looking after their bean seeds since they received them at the Play Barn nearly a month ago.
All the beans germinated and the children observed the growth of the seedling shoots. As the pots are transparent the children can observe the development of the roots. The children have been watering their seedlings and keeping the pots by the window so the plants can get the light they need to make food.
This line of scientific enquiry is called making observations over time. The major working scientifically skill is observing. At one point the children were asked to demonstrate another scientific skill – to make a prediction. This was recorded as thought bubbles. The child’s name is written in the second bubble by the teacher, the child’s prediction is written in the third bubble by the teacher and the child draws a picture of the prediction in the large bubble. I have done on in the style used in school.
The children’s predictions included “it will grow into a sunflower”, “into grass” (perhaps from recalling a previous plant growing exercise), “into a colourful flower”, “a rainbow flower” (use of imagination) and not surprisingly “a beanstalk that grows up to a castle.”
The children have now taken them home but are being encouraged to photograph their plants as they grow and send them into the new children’s blog facility so all the data on bean plant growth can be reviewed in the summer term, predictions evaluated and conclusions drawn.
Here is the first photo report arriving from home showing the measurements being made as
the bean plant keeps growing.
