ingridscience

Rain gauge

Summary
Build a simple rain gauge from a recycled bottle and measure rainfall.
Materials
  • 2L plastic drink bottle
  • scissors/sharp blade
  • ruler, or ruler scale duplicated onto a plastic sheet
  • clear tape
  • clean rocks
  • 2 mini binder clips
  • optional: smaller tube that fits over the mouth of the drink bottle, electrical tape and fine sharpie
Procedure

NOTE: this activity has not been tested with a class of students. Please contact me with suggestions if you try it with students.

Cut the top off the 2L bottle, where the neck widens to the main body.
Tape a ruler on the inside of the bottle, the numbers facing outwards, with zero at the base of where the sides are parallel.
Add clean rocks (to weigh it down) then place in a shady location (to minimize water evaporation) with open sky above (no nearby wall or overhanging branches). Insert the top of the bottle upside down, and clip together.
Make sure the rain gauge is sitting level, then fill with water until the water line is at the zero on the ruler.

Hourly (if there is a lot of rain) or daily/weekly, read off how much rain has fallen. After each reading, either take apart and reset to the water line at zero on the ruler, or record the difference in mm of rain from the last reading.
Tabulate and graph the readings.

Optional set up to get more accurate readings:
Attach a narrow tube to the mouth of the bottle, so that the depth of water will change more dramatically for smaller readings.
Before adding the tube to the system, calculate the scale to add to the tube: calculate the relative surface area of the circles at the top of the 2L drink bottle and the small tube. This will be the relative difference between the spacing on the two scales (e.g. if the 2L bottle circle is 4 times larger, the scale on the small tube will be 4 times more spaced out). Calculate and write a new scale on electrical tape and tape to the side of the narrow tube, before inserting on the mouth of the bottle. Then clip the rain gauge together, as before.

To give a sense of what readings to expect, light rain is only 1mm an hour or less. To read 5mm in an hour it needs to be steady solid rain.

Note that despite the placement of the rain gauge, there will be some evaporation, so readings will not be as accurate as a professional rain gauge. A professional rain gauge style is "tipping bucket" - the rain fills up a little bucket, which is dumped and counted as it becomes full, hence there is way less sitting water to evaporate.

Density, buoyancy and pressure

Summary
Understand density in terms of molecules, and how varying densities determine how buoyant things are and what pressure is.
Materials
  • materials in each of the activities
  • a kitchen scale and graduated cylinder/beaker to measure density
Procedure

Review density:
Density is how heavy something is compared to its size. Density depends on how close the molecules are together and what kinds of molecules make up an object.
In solids the molecules are closer together, so solids are generally more dense than liquids, which are generally more dense than gases i.e. a desk is heavier than the air, a rock is more dense than water. Explained in another way, the rock sinks in water because the mass of the rock is greater than the same volume of water that it replaces. Its weight (the force of gravity pulling on its mass) is greater than the upwards force from the water (force of buoyancy).
Sometimes a solid can float on water e.g. a piece of wood. This is because wood has tubes running through it (filled with sap when the tree is alive) which fill with air when wood is dried out. The overall density of a piece of wood is the combined densities of the wood and the air it contains. If this is less than the density of water, the wood floats. (Some kinds of very dense wood, even when dried out, sink.)

Students try the dancing raisins activity at their desk, in smaller tubes, and think about why they move up and down. Then do a larger demonstration in a cylinder, while discussing why they dance.

Sinking floating challenge 2. Once students have added just the right amount of nails/paperclips/modelling clay to their styrofoam piece to make it float half way down in the water, calculate its density, and compare to the density of water (1g/ml). The answers should be similar.

Discuss pressure:
When a gas (or liquid) is compressed to bring its molecules closer together, it exerts a pressure on the walls of its container.
Do an activity that exploits pressure:
Stomp rocket.
(Pressure in a bottle and popcorn also good pressure experiments to add here.)

Grades taught
Gr 5
Gr 6
Gr 7

Motor free play

Summary
Build motors into electric circuits and use card stock to make fans, buzz saws and spin art.
Materials
  • wires cut from holiday light strings (I do this), or purchased electrical wires, or home made wires
  • batteries, I use AA size
  • small hobby DC motors e.g. from BCRobotix (I use this one) or try CanadaRobotix
  • optional but recommended: motor trays (provide a flat surface to attach card to) I use this one
  • masking tape
  • white card stock and scissors
  • marker pens
  • optional: pipe cleaners and other found light craft materials
Procedure

Before class: if you have motor trays, attach them to the motor shafts
I also spend some time soldering more sturdy wires to the manufacturers motor wires, then zip-typing them to the side of the motor so that they can't be flexed back and forth at the joins.

Students build a motor into a simple electric circuit: a battery and motor, connected into a loop with wires, using masking tape to attach the wires to each component. When the loop of the circuit is closed, the shaft on the motor will turn, but often so fast that it might be hard to see - put a piece of tape on it (or on the motor tray) to see it turn.

Once students have their motor working, show them the card stock and other materials, which they can tape to the shaft of the motor.
Ideas:
Fan - a small circle of card cut to make angled blades, which blow air.
Saw - a small circle of card with a serrated edge can cut through a piece of tin foil or thin paper (held taught).
Colour wheel - add colours to a circle of card. Attach the card to the motor tray to make it spin. The colours blur together.
Spin art - tape a 1/4 sheet of white card stock to the motor tray, then hold a marker to the card as it spins. Cut out afterwards.

Students can also add holiday lights into the circuit - see the helicopter in the last photo.

Notes

If it becomes harder to make good connections, the wire ends may have become tarnished as the metal oxidizes in the air. Sand off the wires until they are shiny copper metal again.

Idea: Use motors to spin discs with different colour segments on them, to understand colour mixing.

Grades taught
Gr 3
Gr 4
Gr 5
Gr 6
Gr 7

Physical changes introduction

Summary
Manipulate materials and decide if the physical change is reversible or not. Then make ooblek.
Procedure

Introduction to physical change stations, followed by discussion of which physical changes are reversible.
Make ooblek - a physical change. It is reversible and can be seen when water evaporates from a small drop of ooblek leaving the powdery cornstarch behind.
Study a physical change, water changing state, in more detail, by measuring the temperature of water in different states.

Grades taught
Gr 2

Anemometer

Summary
Build a simple cup anemometer to show wind speed.
Materials
  • pieces of styrofoam, about 2cm x 2cm x 4cm (blue insulation foam works well)
  • small pen cap or tube, that can be pushed into the end of the styrofoamfoam piece
  • short skewers
  • cardboard egg cartons
  • hot glue gun
Procedure

Prepare the foam ahead of class:
Make a small hole with scissors in the end of a piece of foam and push the tube/pen cap into it. A skewer inserted into the tube allows the foam to spin freely on the skewer.
Make small holes in an egg carton cups and push a skewer through them. Hot glue the skewer in place. (Note: the skewers are a little long in the photo - push them further through before glueing.)

Students assemble their anemometer by pushing the cup skewers into the foam in a circle. Three or four cups work, but younger students may have an easier time spacing out four (one on each side of the foam piece). Ideally the cups are all facing the same direction - help younger students to assemble, and allow older students to experiment with cup placement.
Insert a skewer (with no cup attached) into the hole that the pen cap/tube makes in the foam.

Blow into the cups to turn.

Try experimenting with different numbers of cups, and different strength of breath.

A weather station anemometer has metal cups which are weather-proof. The speed of the spinning cups is recorded as wind speed.
Real anemometer image: https://education.nationalgeographic.org/resource/anemometer/
https://www.environmental-expert.com/products/eml-model-wsu1-wind-speed…

Notes

Wind speed with a ping pong ball on a string: https://www.howtosmile.org/resource/measuring-wind-speed

Grades taught
Gr K
Gr 1

Mountain landforms and their erosion

Summary
Build models of mountains from a simple contour map, read contour lines on a large map, then use sand and water to show how erosion shapes landforms.
Procedure

Sit around a paper contour map of local mountains/hills e.g. Vancouver North Shore.
Map with heights also coloured: The colours help us see the heights, but we don't need it with the lines, or contours. The shape of the lines show the shape of the land.

You'll build a model of a mountain from a contour map.
Demonstrate then run Landform models.

As students make their model they bring it, and their corresponding contour map to the tarp, and lay them down to build two identical landscapes - one of the landform models and one of the corresponding contour maps.
As a class, look at the landscape and the contour maps. Refer back and forth while discussing and highlighting features of a contour map
e.g. When lines are close together, a slop is steep
e.g. When lines are far apart, a slope rises gradually
e.g. A valley forms between slopes, and the contour lines go up and back across the valley
e.g. a bay, a peninsular, a cliff
Refer back to the local paper map, and find these landform features.

Explain that Erosion makes these shapes in the land.
Water, ice and wind wear away parts of the land to make valleys and other landform shapes.

Watch erosion in action with the sand and water erosion activity, at table groups of four, or as a demonstration.
Note that the Erosion model is sped up a lot - valleys form over thousands or millions of year (depending on the rock type).

Maps needs to constantly change as the landscape changes.

Grades taught
Gr 2
Gr 3
Gr 4

Landform models

Summary
Use a simple contour maps to assemble 3D models of mountains with valleys. Combine class landforms into a landscape that can be compared to a contour map.
Materials
  • simple contour map of a mountain or hill on a half-sheet of paper, two identical copies
  • ball of playdough, about two cups
  • plastic tubes to use as rolling pins (they don't stick to the play dough as much as wood)
  • plastic knife or butter knife
  • table mat to protect the table from play dough and knives
  • scissors
  • tarp to lay landscapes on
  • optional: toothpick, if the contour map is more complex e.g. two peaks
Procedure

Ahead of the lesson: print simple contour maps on half sheets of paper (see attached file). Each one is a little different e.g. some have steeper slopes; for capable students include river valleys (E1 and E2 on attached file). Make a duplicate copy of each contour map.

With students, look at a topographic map that shows the height of land in different colours, either on a large paper map, or projected
e.g. North Shore mountains of Vancouver
e.g. this map of Hawaii: https://commons.wikimedia.org/wiki/File:Hawaii_Island_topographic_map-f…
On Hawaii map: ask students how many mountains there are on the map (two or four).
On any map with colours: point out the colour changes as the height changes.
On any map: Then point out the lines - these are called contours and show where the land gets higher. The colours are not needed with these 'contour lines'.
Then optionally look at a map that shows only the contours, lacking colour changes with height e.g. this map of North Vancouver and nearby Islands: http://www.canmaps.com/topomaps/nts50/toporama/images/092g06.gif
Show them the contours and tell students that they show how high the land is. Their spacing tells us how steep or gentle a slope is, and where there are river valleys and plateaus.

Tell students they will make their own model of a mountain from a simple contour map.
Demonstrate the activity, before students run it themselves (pairs work well):
Cut out a contour map around its outer edge, while the other student rolls out about half of the play dough to about 1cm thick, or until it is large enough to fit the contour map on it.
Lay the cut piece (showing the shape of the lowest level of the contour map) on the play dough and use the knife to cut out the shape. Lay the shape to one side of the mat.
Now, cut out around the next smallest contour line, and roll out a new piece of play dough (students can switch roles). Lay the (now smaller) contour map on the new rolled-out play dough and cut out the (new) shape. Lay the new play dough shape over the first one, using the duplicate contour map, to show where to lay the second layer over the first layer.
Repeat with the following contour lines, cutting out their shapes in play dough, and using the un-cut contour map to show how to align the layers on the growing mountain.

(For older students, more complex mountains with two peaks can be made.) If there is any doubt how to align one layer on the next, use a toothpick to help:
Before picking up the first paper contour cut-out, stick a toothpick through the paper and into the play dough in several places. When subsequent layers are made, push the toothpick through the same holes in the paper into the rolled-out play dough before removing the paper. The toothpick holes in the play dough can be aligned to place each layer in its proper position.

Once their mountains is made, students can cut their duplicate contour map along the outer contour line only, then bring their mountain and duplicate contour map to the tarp, where they are placed for display on separate halves of the tarp. As new mountains are added, place them next to the previous ones, and place the corresponding contour maps in equivalent positions in their own area. The growing landscape of model mountains will be reflected in the growing contour map assembly next to it.
(As students understand the relationship between the growing mountain landscape and the adjacent contour map, they can help direct where to place the contour maps correctly.)

As a class, look at the landscape and the contour maps. Refer back and forth while discussing and highlighting these features of a contour map:
The mountains look like islands in the ocean (the tarp is the ocean water).
Where are the steep slopes and the gentle slopes on the play dough mountains? Look at the contour maps to see what the lines do [lines are close together on steep slopes and far apart on gentle slopes].
Optional (and with warning to students that their creations will be modified): smooth out the sides of each mountain, so they look more like real mountains, commenting that the lines show the heights, but real mountains don't go up in steps.
Ask students to find valleys on the play dough mountains, which rivers might run down. Then show the same valleys on their contour maps - the contour lines have a distinctive shape, curving up and back, in a valley. Show them river valleys on a real map/the projected map (which likely also has a blue river line).
Refer back and forth between the landscapes while discussing and highlighting landforms that the students know about (e.g. mountains, hills, plateaus, valleys, deltas).

As a class, look back at a real contour map (preferably in an area that students are familiar with e.g. the same Cypress mountain map with the Sea-to Sky highway) and try to read the mountains: the steep slopes, the gentle slopes, the narrow river valleys (formed by water) and wide river valleys (formed by glaciers).

Optional and advanced: Students modify their mountains, then make a new contour map of their new mountain (not tested with a class).

Grades taught
Gr 2
Gr 3
Gr 4

Heat Convection

Summary
Visualize heat convection, then make a device that turns with the convection heat from a small candle.
Procedure

Demonstrate that heat moves upwards in a fluid such as water with the Heat convection demonstration.
Use heat convection to make a candle pinwheel that gracefully turns with the heat from a candle.

If time, demonstrate that the candle needs air to burn by putting jars over it - see candle combustion

Convection determines the Earth's climates and the living things that inhabit it:
1. Convection currents in the sun bring heat to the sun's surface (which is radiated through space to Earth):https://www.nasa.gov/wp-content/uploads/2023/03/655928main_solar-anatom…
2. Convection inside the Earth happens in the mantle below the tectonic plates. The convection currents drive the movement of the tectonic plates, forming mountains and volcanoes. https://en.wikipedia.org/wiki/Mantle_convection#/media/File:Oceanic_spr…
3. Ocean convection currents move heat around the Earth. Along with the intensity of the sun’s rays, the warmth carried by ocean water gives rise to Biomes, each with their own climate and living things adapted to that climate. https://svs.gsfc.nasa.gov/10841
4. Atmospheric convection currents, caused by the sun’s rays heating the Earth, which heats the air above it, gives rise to winds and weather systems: https://www.researchgate.net/figure/The-six-major-air-cells-of-the-Eart…

Grades taught
Gr 2
Gr 3
Gr 4

Candle convection pinwheel

Summary
Make a device that spins with the convection heat of small candles.
Materials
  • card stock, 15cm/5.5inches square
  • optional: compass to draw a circle on the card, only if you want students to practice using a compass
  • scissors
  • little tube or pen cap (test first, and clip much of the length off if necessary)
  • floral wire, or wire thick enough to stand up on it's own, but bendable with hands, about 40cm
  • masking tape, about 15cm
  • two small birthday candles, or similar
  • modelling clay, two small pieces
  • lighter (for teacher use)
  • optional: instructions (see attached file) for each student group
Procedure

Bend the end of the wire into a triangle, and tape to the desk. Bend the long straight end of the wire upwards. This is the stand for the spinner.
Cut the square piece of card stock into a circle (optionally using a compass to draw a circle on the card first). It does not have to be exactly circular, but make as large as possible.
Cut from the edge of the circle partways toward the centre, to make blades (telling them half way is fine if students might cut too far). Six or eight blades seem to work best.
Use a straight edge (ruler or book) to fold half of each blade partly upwards (see photo). Or fold by hand but make sure the crease is tight.
Make a small hole in the centre of the circle with the scissors (or pre-punch a central hole in each piece of card for students) then push the tube/cap through.
With the blades pointing down (may need to reverse the direction of the tube/cap), place the pinwheel on the end of the wire. Make sure the wire is not touching the edge of the tube/cap except at the very tip (keep friction to a minimum).
Use two small pieces of modelling clay to secure the candles on the desk under the pinwheel, making sure there is some space between the pin wheel and the candle (so the paper does not catch fire). One candle can work too if everything else is optimal, but starting with two gives the best chance of pinwheels working.
An adult lights the candle. Wait for the pinwheel to start turning. Do not leave unattended.

If a pinwheel does not turn, here are some troubleshooting ideas:
Make sure the wire tip is only touching the very end of the tube/cap. Any rubbing of the wire along the length of the tube/cap will create too much friction for the wheel to turn. Bend the wire so that it is perfectly vertical inside the tube/cap and only touching at the very tip throughout an entire turn of the pinwheel.
Make sure the unfolded part of the blades of the pinwheel are not sagging, and bend upwards until horizontal if they are. (The paper curls down a little from the initial heat of the candle.)
Adjust the angles of the folds in the blades, so that they are not too vertical and not too horizontal. (The angle with the incoming rising heat is important.)
If students are walking around the classroom a lot, the air currents they create will disturb the heat convection currents that make their pinwheel turn. Keep them seated as much as possible so that the candle flames are directly upwards.

Once students have made a candle pinwheel that works from these instructions, and they understand the need for the angled blades, they can make shapes of their own to test and troubleshoot.
As long as they have a large enough surface area of sloping blades and the card is balanced on the wire, it should turn. One student group made a heart shape that was a little unbalanced, but by moving the place that the tube was pushed through, and with with the help of my lighter at a critical point in its rotation, I could add enough heat to push it past its sticking point.

How it works:
Air heated by the candle flame flows upwards by convection.
The hot air rises and meets a sloping blade of the pinwheel, and pushes against it (the air molecules bang into the blades). Because of the slope of the blade, the blades are pushed sideways and because they are part of a wheel, they rotate.

Once everyone's pinwheels are turning, turn out the classroom lights for a beautiful scene.
To consolidate how it works, students can draw their pinwheel, showing how the heated air rises and hits the blades (blow out candles first).

Additional experimentation for students to try out:
Does it make a difference which direction the blades are folded relative to the incoming convection heat? i.e. can they angle up instead of down?
Does it make a difference how many blades there are?
Try a completely different shape: a flower or a starburst with many blades.

Good activity to follow this: candle chemistry.

Pinwheel shape idea from https://www.youtube.com/watch?v=_TRKsKMuYZ8

Notes

A spiral can also work, but the tube system is too much friction. To reduce the friction enough, make a tiny dent in the centre of the paper spiral and balance this on the tip of the wire. (But danger of the spiral of falling off and into the flame.)

Demonstration for Ks.

Grades taught
Gr K
Gr 1
Gr 2
Gr 3
Gr 4
Gr 5
Gr 6
Gr 7

Tides model

Summary
Use a gravity well to model the pull of the moon on water, which causes the tides.
Materials
Procedure

Set up the gravity well and add a golf ball and about 20 marbles to it.

Tell the students that the golf ball represents the Earth, and the marbles represent the ocean water.
The gravity of Earth (modelled by the well in the fabric) attracts the water and holds it in place, just as gravity pulls on us and stops us from floating away.
We can model the Moon orbiting the Earth by pushing our hand down into the fabric to make a second well in the fabric, and circling it around the "Earth". As our hand moves, the marbles roll slightly towards the "Moon" and follow it as it orbits.
(Note that it is tricky for students to make the right amount of gravity (pushing into the fabric the right amount) and orbiting at the right speed (moving the hand in a circle around the golf ball), to make the water follow the "Moon" without leaving "Earth". Demonstrate how to make it work.)

The real Moon's gravity also pulls on the oceans, not so much that the water leaves Earth, but enough to make it follow the Moon in its orbit. The water nearest to the Moon will bulge out.
Tides on Earth are a result of this gravitational attraction of the Moon on the Earth's oceans, with additional factors:
The Moon causes the water to bulge out on the side nearest it. Because of the difference in the gravitational pull of the Moon on the near and far side of the Earth, water is also pulled out on the opposite side from the Moon.
The Earth rotates under the tidal bulges, so each point on earth moves through two high tides in one day.
The sun also pulls on ocean water. When the sun and the moon are lined up (new or full moon) the tides are higher (called spring tides). This happens twice a month. At half moon, the sun and moon are pulling water in different directions, so the tides are lower (neap tides).
The land masses and the varying ocean depths mean that the tides are on a more complex cycle than this (https://oceanservice.noaa.gov/facts/moon-tide.html), but they all originate with the pull of the moon on water.

Animation of the tides:
https://oceanservice.noaa.gov/education/tutorial_tides/media/supp_tide0…
https://oceanservice.noaa.gov/facts/springtide.html
Image at https://www.ck12.org/earth-science/Tides/lesson/Tides-HS-ES/

Another interesting phenomenon occurs with the gravity well where if the hand is moved fast the marbles will fly out in a line following the hand. This is a model of the Roche limit, how a satellite breaks up when it gets to close to a planet. See more on page 23 of https://www.spsnational.org/sites/default/files/files/programs/2012/soc…

Also note that students will want to explore more with the marbles, picking them up to make them orbit - follow this activity by using the gravity well more to explore orbit shapes and speeds.

Notes

Combine with moon phases and barnacles for a lesson on tides.

In depth explanation of Pacific Northwest tides (I haven't attacked it yet): https://faculty.washington.edu/pmacc/LO/tides_background.html

Grades taught
Gr 3
Gr 4