ingridscience

Discuss what a solid, liquid and gas are.
A solid is hard. The particles are packed together so tightly that we cannot push through it and we can see it.
A liquid we can see but the particles are further apart, so it can flow and we can move it around with our hand.
A gas we cannot see as the particles are so far apart. But we can feel the particles hitting our hand (wave hand through the air).

Students are given a clipboard holding their scavenger hunt worksheet, and a pencil.
Students hunt around the classroom or school grounds looking for solids, liquids and gases. They write down each item and check off whether it is a solid, liquid or gas. They should try and find at least one of each state.
Gather to review and discuss.

Could be used as a review for older students - ask them to look around from where they are sitting and find a solid, liquid then gas.

Prepare the activity:
Lay a piece of cling wrap over the top of the plastic tub. Use masking tape to secure the cling wrap most of the way round, leaving it open the last 1/4 of the length.
Add the salt and food colouring at one end of the plastic tub (make separate piles). Place the pot in the middle of the tub.
Alternatively, students can later add the salt as you visit each of their tables to set up the water cycle model.

In class:
Boil the water, then immediately add it on top of the salt to a depth below the rim of the pot (it will not work unless the water is only just boiled). Clip the lid shut by securing the cling wrap with binder clips. The cling wrap may balloon up. Place the marble in the middle of the cling wrap, and push the cling wrap down, so that the marble is directly over the pot.

After 5 mins or so, drips of re-condensed water will fall from under the marble into the pot. After 10 or 15 minutes there will be enough drips of water in the pot to have made a puddle.

The students can optionally taste the water in the pot ("the lake") and the tray ("ocean") - give them a Q tip to dip first in the lake water and taste, then use the other end of the Q tip to dip in the ocean and taste. The ocean water is salty and the lake water is fresh. Only the water evaporates from the ocean - the salt is left behind. The food colouring also stays in the ocean, but does not appear in the lake.

Each student makes a bracelet with coloured or shaped beads. The beads are threaded in an order that represents the stages of the water cycle.
With with smaller pony beads we repeated the cycle four times and with large shaped beads we used one of each bead shape.
Once made, an adult can secure their bracelets on each student's wrist. By tucking the pipe cleaner ends inside the adjacent beads, an unbroken circle of repeating bead colours represents the endless cycling of water on earth.

If using the worksheet and small coloured beads:
Cut a short length from each student's pipe cleaner before class.
Distribute the short lengths of pipe cleaner and one set of the 6 bead colours, to each student.
Students thread the beads on the short piece, in the agreed colour order for each water cycle word. Tape the short bead sequence on the worksheet next to the water cycle words. This key shows which colour represents each stage of the water cycle.
Then students use their longer pipe cleaner piece and more beads to make their bracelet, in the correct bead colour order, and repeating several times.
(Alternatively, coloured pencils/markers can be used to show the bead colours of each water cycle word on the worksheet).

If using the worksheet and larger wooden bead shapes:
Draw the bead shapes next to each water cycle word.
Then make the bracelet in the correct order of bead shapes.

Optional: start by reviewing the states of matter, while asking students to find examples in the classroom. Solids have a fixed shape and are hard. Liquids can change shape, but always take up the same amount of space (same volume) as they flow in their container. Gases change shape and fills the space they are in (so change volume). Some students might mention plasma, the 4th state of matter.

The particles (molecules or atoms) are arranged differently in different states of matter. Tell students that they will model the particles in each of the three states of matter. They are each a molecule. Ask them to stand in an open space of the classroom.
In a solid the molecules are packed tight, held together by strong bonds. Ask students to model a solid by linking arms with their neighbours, so that they are packed tight together in a group. The individuals can jiggle a little, but the group maintains its shape.
As a solid gains energy the molecules gain energy and can move around more. They are still bonded to each other, but more loosely. Ask students to model a liquid by spreading apart and moving around more, but always touching at least one other student with an outstretched arm. The bonds between molecules break and form continuously, so that the group stays together but can move and change shape, like a liquid.
As a liquid gains even more energy the molecules gain enough energy to move completely apart and evaporate. Ask students to break all bonds with each other and move around the room, spreading out to fill the room. Students can be asked to lose energy and become a liquid again (condensation), then a solid (freezing).

For younger students, simplify the language:
Stand up close together, arms linked. Stay still. You are not moving. You are stuck together, so you cannot change shape. I can see what shape you are. Which state are you? Solid.
You have a bit more energy. Now you can move around a little more. Walk around, but always stay touching at least one other person. So you can change shape but stay the same size. Which state are you? Liquid.
Now you have even more energy. You can now move around even more, let go of each other. You now can change shape and size. Which state are you? Gas.

Videos of educators/students acting out states of matter:
https://www.youtube.com/watch?v=FUa3F2CfbPE
https://www.youtube.com/watch?v=rmBRpuXI5AA

Image of particles in the three states: http://wps.prenhall.com/wps/media/objects/943/966267/fig10.gif
Longer cartoon video of the particles in solids, liquids, gases at https://www.youtube.com/watch?v=guoU_cuR8EE

Each student: open a small baggie and add 2 tablespoons whipping cream, 0.5 teaspoons sugar and 2 or 3 drops of vanilla essence. Seal. Double bag the mixture by fitting this bag neatly inside a second baggie. Hang the baggies down the inside of a large container (500/650 g/ml) and fold the ziplock top over to the outside of the container. The bottom of the baggies should be hanging near the bottom of the inside of the container. Two students can hang their bags on each side of the same container.
Each pair of students: add 2 tablespoons of salt and about 10 ice cubes to a the container. The container should be about 2/3 full.
Snap the lid on the container over the top of the baggie.
Holding the lid on, shake the container for 5-10 minutes (yes, it takes a while), until the cream turns solid. (Double bagging ensures that punctures of a baggie by the ice cubes do not go through both layers.)
Eat out of the baggie with a spoon - quickly before it melts again!

Ice cream is frozen cream with air pockets that make it light.
The air is added as the cream is shaken.
The temperature is reduced enough to freeze the cream by adding the salt. The salt lowers the freezing temperature of water, so that as the ice melts, liquid water lower than zero centigrade surrounds the cream, causing it to freeze.

Visit a forest, park or other area with native plants. Teach students the native plants (and animals) for the area.

Scavenger hunt:
Clip one copy of each card to its respective plant before the lesson.
At the lesson, give each student a card, ask them to find the same card pegged to a native plant.
They can stack the cards and peg them together, before getting another card, or helping others find theirs.

Bingo:
Give students bingo boards (each a little different from each other). Students call Bingo! when they have found all the plants on their sheet.

iSpy:
iSpy cards can be the same for each student, and the group can work together to spy each of the plants.

Optional discussion on how native plants are used by Indigenous cultures:
fern: young leaves for food (called fiddleheads - look for them in your food market)
red flowering currant: berries for food
salmonberry berries: for food
salal: berries for food, leaves for a cooking flavour
skunk cabbage: leaves for lining berry baskets
cattail: leaves woven into mats and seeds for pillows and wound dressings
moss: for bedding and pillows
iris: leaves braided into snares for catching large animal prey
fir tree: wood for fuel, and for making spear handles and spoons and other tools
cedar tree: wood for canoes, houses, totem poles, arrow shafts as well as fuel; cedar bark for baskets, rope, mats and woven with wool for clothes; roots for baskets and ropes.

Hand out Doulas fir cones to look at and retell Indigenous story about Douglas Fir cones:
Long, long ago there lived a mouse in the forest. The mouse was fearful all day and all night, for the sly fox always tried to catch him and eat up him. The mouse was very clever and was able to hide from the fox for a long, long time. But one day, he let his attention wander, and before he knew it, the fox was right there! The mouse was very scared and ran off as fast as he could. But he knew the fox was faster, so frantically he searched for a place to hide. He spied a cone that he thought was big enough to hide him, so he scurried inside. Well, he was hidden well enough that the fox couldn't find him, but really the cone was too small. And to this day, you can see the hind legs and the tail of the mouse sticking out from the Douglas-fir cone, where he is STILL hiding from the fox!
Students can find their own Douglas fir cones until time to go back to school.

Bog information:
Bogs are a valuable natural resource. They store water, which prevents flooding by slowing the water entering streams and rivers. They are a carbon sink, as the plants in them do not decay. They are natural filters.
Bogs have unique ecosystems - they are low oxygen and acidic - bog plants are adapted to live in this environment.

Introduction: the chemistry of the stream water determines how much life can grow in it. First we will measure how much oxygen is in the water (http://www.lamotte.com/pages/common/pdf/instruct/5963.pdf). Like us, the living things in the stream need oxygen. We breathe oxygen in from the air. Animals that live in the water use oxygen that is dissolved in the water. (http://tellus.ssec.wisc.edu/outreach/teach/ideas/kotoski/Minifact_Sheet…). Second, we will measure the pH of the water (or how acidic it is). If the water is too acidic (or too much in the other direction, too alkaline) living things will die (http://tellus.ssec.wisc.edu/outreach/teach/ideas/kotoski/Minifact_Sheet…).

Within a designated area, students explore the stream to find landmarks (e.g. waterfall, bridge), then choose a part of the stream that they would like to sample. First they collect water in a tube for dissolved oxygen testing, and then collect the tablets from an adult. While these tablets are dissolving, they can collect a second tube of water from the same place for pH testing, and then get a drop of pH indicator solution.
Students record their pH and their dissolved oxygen level for the area of the stream that they tested. Students can draw a map of the stream, with landmarks, and mark where they sampled from. They can also mark the location and readings obtained by a friend.
When all the students have made their measurements, the group hears all the readings and then discusses how healthy the stream is for living things. (In this class: dissolved oxygen was 4ppm -sufficient for some, but not all, life; pH varied from 6.5 to 7.5 - able to support a variety of living things).

Extension of experiments on dissolved oxygen - use the tablets to measure the dissolved oxygen in a sample of pond water, and track the reduction in dissolved oxygen as it is used by the living things in the pond water (experiment suggestions in ref 4)

Find a good collection site at the pond. Around the base of plants, rather than open water, tends to be more fruitful.
Fill a large tray with pond water for each student group.
Using a fine net, students scoop from the pond or stream near to plants then invert the net into the large tray.

Alternatively, the teacher collects pond water samples and brings them into the classroom in white tubs (so that the contents can be seen easily).

Students transfer organisms they find in the large tray to smaller trays with a pipette, then use the magnifiers to look at them closely.
Students are assisted in identifying the pond invertebrates they find.

Try these web pages for identification keys:
For Daphnia and similar species, cyclops and shrimp: Page 46 of https://www.britishecologicalsociety.org/wp-content/uploads/Brine-Shrim… Daphnia photo: https://www.britannica.com/animal/water-flea
For most species you will find: https://www.microscopy-uk.org.uk/pond/ Make sure you click on "arthropods" as you'll find a lot of these, and then "other insect stages" for larger specimens.

Organisms students with me have found:
At Central Park pond, we identified Cyclops, freshwater shrimp, worms and Daphnia. In our back yard pond we identified Daphnia, leeches, caddisfly larvae, cyclops, worms, and sometimes stentor. At Jericho we identified Daphnia, water beetles, water boatmen, worms and shrimp. At Trout Lake we found Daphnia, worms, mosquito larvae, water mites, mayfly nymphs or something similar. Water plants and seeds also caught may be identified.

Gather as a group and add each organism found to a white board, then with discussion, link who eats who to form a food web.
Simply put, pond organisms eat anything smaller than them. Add microscopic bacteria and algae, eaten by the tiny pond organisms.
Add other animals and plants seen around the pond.
Optional: play bird sounds for local birds noticed.