ingridscience

Bread: test ingredients for making gas

Summary
Test pairs of ingredients for making bread, to find out which ones make gas, which causes dough to rise.
Science topic (2005 curriculum connection)
Life Science: Plant Growth and Changes (grade 3)
Physical Science: Chemistry (grade 7)
Materials
  • rack with several 15ml tubes
  • masking tape and pen for labelling tubes
  • ingredients to test: yeast, sugar, flour, salt (optional: oil - its messy)
  • very warm water in a squeeze bottle for each table
  • coffee stir sticks
  • worksheet (see attachment)
Procedure

Dough will rise as a chemical reaction happens in it: a gas is made, and the bubbles push out on the dough, making it rise.
[While we wait for our dough to rise] we’ll experiment with the ingredients to find the ones that make a gas and make the dough rise. You might have an idea already and can test your idea.

We’ll mix pairs of ingredients.
Choose a number in the table (attached below), then find the corresponding pair of ingredients.
Add 1ml of each of the ingredients using the stir sticks (do not use the same stir stick in different ingredients).
Then make other tubes for other pairs of ingredients.

Once all the tubes are ready with their dry ingredients, hand out bottles of warm water.
Fill to the 7ml mark and use a new stir stick to stir well.

Wait at least 5 mins for results, then ask students to record the ml of gas in each tube in the table.
Ask students to compare their data to conclude which combinations make the most, and some gas.
Expected results:
The yeast and sugar make enough gas for bubbles to likely spill over the top of the tube.
Yeast and flour make some gas bubbles too.
Yeast and flour/oil/salt make very few or no gas bubbles (probably because the yeast has some sugar stored in it already).
Note: the numbers on the tubes in the photographs above do not correlate with the numbers in the attached table, as the table has since been simplified.

Explanation:
The yeast breaks apart sugar molecules to form ethanol (which evaporates off) and carbon dioxide gas, which makes the bubbles. (Chemical reaction can be modelled.)
Flour is made up of chains of sugar molecules. The yeast can break up these chains, then make gas from the sugar molecules.
Yeast has some sugars stored in it, so can make a few carbon dioxide bubbles from these stores.

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

Posting game

Summary
Students run around to post cards in pots that are placed outdoors around a school or park. The cards can be on any topic e.g. smell molecules to match with pots placed near scented plants; pollinators to match with pots placed near plants that they pollinate; water cycle words; life cycle stages to post in pots of different animals; plant group classifications.
Science topic (2005 curriculum connection)
Life Science: Needs of Living Things (grade 1)
Life Science: Animal Growth and Changes (grade 2)
Life Science: Plant Growth and Changes (grade 3)
Life Science: Diversity of Life (grade 6)
Life Science: Ecosystems (grade 7)
Materials

Posting game with smell molecules:

  • a park or yard with smelly plants, or bring smelly plants in to place next to the pots (e.g. lilac, rosemary, lavender, apple, use grass and cedar on the site)
  • tubs with posting holes, with an image of a smell molecule on each, corresponding to the smells given off by each plant (e.g. for above plants use geraniol, eucalyptol, linalool, isoamyl acetate, hexenal, pinene). use images in attachment
  • additional images of the smell molecules on small squares of paper, about 10 per student - use attached file

Posting game with pollinators:

  • a park or yard area with flowering plants, or bring flowering plants in to place next to the pots
  • tubs with posting holes, each with an image of a pollinator (e.g. bee, beetle, fly, butterfly, humming bird)
  • additional images of the pollinators on small squares of paper, about 10 per student

Posting game with water cycle words:

  • a park or yard area
  • tubs with posting holes, each with a water cycle word (e.g. evaporation, water vapour, condensation, cloud, precipitation, run off)
  • additional copies of the water cycle words on small pieces of paper, about 10 per student, laminated if to be used in the rain

Posting game for plant classification:

  • a park or yard area with different kinds of plants
  • tubs with posting holes, each with an image of a plant group (e.g. moss, conifer (gymnosperm), monocot, flowering plant)
  • additional images of the plants on small squares of paper, about 10 per student
Procedure

Smell molecules posting game
Spread pots around the site, each displaying a smelly molecule image. They should be placed near the plant that releases their smell molecule, or bring in plants to place next to each pot. I used these smell molecules and plants (molecules pictured in attached file "table of smell molecules and plants for posting game"):
A sprig of rosemary next to a pot displaying the eucalyptol molecule.
A sprig of lavender next to a pot displaying the linalool molecule.
A sprig of lilac (or any sweet-smelling flower such as rose or geranium) next to a pot displaying the geraniol molecule.
An apple (or banana or other ripe fruit) next to a pot displaying the isoamyl acetate molecule.
Next to some grass (or any green leaves that release the mown-grass smell), place the pot displaying the hexenal molecule.
Next to a cedar (or other evergreen tree), place the pot displaying the pinene molecule.
Other ideas for molecules and source match: https://www.thoughtco.com/aroma-compounds-4142268

Shuffle the molecule cards, then give one to each student, but ask them to wait until everyone has a card before starting. Instruct them to post their card into the pot with the same molecule on the top. Some of the molecules look similar, so they should check the match carefully. Ask them to also smell the plant next to the pot to see what the molecule smells like.
The students can start out all at once. As they each return from posting their molecule card, give them another card to post. Keep distributing the cards, one by one to the students that return, until all the cards are posted. (Or end earlier if needed.)

Discussion:
Bring all the pots back to the group, and ask students which molecules looked similar to them (e.g. eucalyptus and pinene, or linalool and geraniol). Although they look similar they have different smells. Our nose can distinguish between the smells by this mechanism: each smell molecule fits into a different molecule in our nose. Once the smell and receptor molecule dock with each other, they trigger a neuron to fire which sends a signal to our brains to sense a smell. (Actually it is a little more complicated as smells are usually made up of more than one smell molecule, and the combination of receptor molecules that are triggered induces the distinct smell sensation in our brain.)

Discussion on how plant smells are used to communicate with animals:
Sweet smells are given off by flowers to attract pollinators to them.
Smells like eucalyptus and pinene repel insects, to discourage insects from eating the plants that release them.
The ripe fruit smell (isoamyl acetate molecule) attracts animals to eat the fruit (and hence distribute the seeds in them).
The grass smell (hexenal) is made when green plants are crushed or damaged. It is thought to induce defence responses in neighbouring plants so that insect damage to them is limited.

Pollinators posting game
Short discussion/review on why flowers are different colours, smells and shapes - to attract different pollinators. The pollinators collect nectar and/or pollen from flowers for themselves. At the same time they brush against pollen and move it from one flower to another, so fertilizing the eggs, and making seeds.
Bees, butterflies, humming birds, moths, flies, beetles and bats all pollinate flowers. Some flowers are pollinated by only one kind of pollinator, and some are pollinated by many kinds. (Wind is also used by many plants to simply blow the pollen between them.)

Place pollinator pots, each displaying an image of a pollinator, next to a flower that the animal would visit (or bring in flowers to place next to the pots):
Bee - attracted to bright coloured flowers with a sweet smell. The flower can be any shape, including tubular as long as the bee can fit into it. (They also use nectar guides: visible or UV patterns that guide the insect to the nectar.) I used a bluebell.
Butterfly - attracted to bright coloured flower with an odour. The flowers are often wide, so the butterfly can land on it, but the butterfly can also fit its proboscis into a tubular flower. Butterflies use patterns or nectar guides to find the pollen. I used a marigold.
Fly - attracted to white/green/yellow/brown coloured flowers, often with funky/putrid odour (not sweet). Flies have a short tongue, so need a bowl-shaped flower. I used a buttercup (bees and beetles also pollinate buttercups).
Humming bird - red/yellow/orange coloured, odourless, tubes/funnels/cups. I used honeysuckle.
Beetle - white or green coloured, odour can be absent or strongly fruity, large bowl shape to crawl into. I used a dogwood flower.
Moth - dull red/purple/pink/white coloured, strong sweet smell emitted at night, various shapes.

Give students one image card with a pollinator image on it. Ask them to post it in the correct tub, before coming back for another one.
Students keep posting until the picture squares run out.

Water cycle posting game
Arrange the pots in a large circle, in the order of the water cycle events (evaporation - water vapour - condensation - clouds - precipitation - runoff).
If it is wet outdoors the water cycle words to post should be laminated.

Plant classification posting game
Place the pots next to the same plant as on the image.

Life cycle posting game
Pots display different kinds of animals, for example: fish, bird, reptile, amphibian, mammal, insect, crustacean.
Cards display different stages of life cycles, for example: egg, live birth, juvenile, larva, nymph, pupa, adult.
Students post a life cycle stage in a pot who's animal has that stage. There will be more than one pot in several cases. Challenge students to find a different pot if they get the same card again.
Once the cards are used, dump out each pot and arrange the (correct) cards in a circle (over images if possible) to show the life cycle of that animal, filling in any gaps with extra cards. Move the incorrect cards to the correct animal life cycle, without dwelling on the mistake.

Notes

Tip: if doing more than one posting game in the same day, stick the second set of cards on the underside of the lids.
Use posting game for types of colloids (foams, aerosols, emulsions, gel, sol).

Grades taught
Gr K
Gr 1
Gr 2
Gr 3
Gr 4

Plant Secrets

Summary
Starting with a seed, shows the cycle to plants, flowers, fruits, seeds. Each stage has a secret, which is the next stage.
Curriculum connection (2005 science topic)
Life Science: Plant Growth and Changes (grade 3)
Type of resource
Book
Resource details

Plant Secrets by Emily Goodman. 2009. Published by Charlesbridge.

Notes

Pretty good for the plant cycle. Will keep looking for better.

Mason bees

Summary
Look at mason bee cocoons then place them in a mason bee house installed near early flowering plants.
Science topic (2005 curriculum connection)
Life Science: Plant Growth and Changes (grade 3)
Materials
  • mason bee cocoons e.g. West Coast seeds product
  • mason bee house e.g. bought or home made
  • an East facing tree or wall, where the house can be placed out of reach
Procedure

Hand out magnifiers and practice using them by looking at fingerprints. Take time to make sure every student is using it correctly.

Tip the cocoons out of their box and place on students' desks, so that they can look at them closely.
Before half an hour is up, return the cocoons to their box, and take outside to place in the installed mason bee house.

Explain how the bees will hatch within a couple of weeks (the males first). Then they will mate, and the females will lay eggs in the tubes of the house. Over the following months, into the Fall, the eggs will hatch, a larva will grow, and eventually make a cocoon to protect it through the winter. The adult bees will hatch out next early Spring. (Cocoons that have been harvested and sold are kept at fridge temperature, so that the bees do not emerge until the cocoons are placed outside.)

Grades taught
Gr 2
Gr 3

Plants interacting with animals

Summary
Study various animals that plants interact with: look at worms, look at a herbivore jaw, make a bird feeder.
Curriculum connection (2005 science topic)
Life Science: Plant Growth and Changes (grade 3)
Procedure

Plants are not isolated - they interact with other living things.
Choose a part of this lesson plan.

Plants and worms:
Use magnifiers to closely observe worms. Label a drawing of a worm.
Class discussion on structures of worm (hearts, breathe through skin).
How are worms linked to plants? They make the soil that the plants grow in. Look for dark soil being made in the gut of the worm.

Plants and herbivores:
Plants are tough. Animals that eat them need specialized teeth to crush the tough plant cell walls.
Sit at carpet and look at the teeth in herbivore jaws. Molar means “millstone”.
Show deer skull and jaws fitting closely together to grind the plants.

Show some of the plant structures with plant printing. The xylem and phloem vessels that make the branching patterns have cell walls made of tough cellulose. Cellulose molecules make up all the cell walls of plant cells. Herbivores can’t break down the cellulose. They have to smash open the cell walls to get to the sugars and other nutrients inside.

Plants and birds:
What do birds eat? Seeds. (Reference seeds studied, or seeds planted by the class.)
Make bird feeder with pine cone, lard and seeds.

Grades taught
Gr 3
Gr 4
Gr 5
Gr 6

Measuring and estimating plant height

Summary
Use plants for measuring and estimating. I used the butterfly garden at Gordon.
Science topic (2005 curriculum connection)
Life Science: Plant Growth and Changes (grade 3)
Materials
  • Worksheet (attached)
  • Clipboard and pencil
  • Tape measure or metre rule
Procedure

Students work singly or in groups on the worksheet. Start different groups at different numbers.

Attached documents
Grades taught
Gr 3

Plants: vessels in plants

Summary
Use a microscope to see the cells that transport water up the plant. Print with plants, which highlights the vessels.
Curriculum connection (2005 science topic)
Life Science: Plant Growth and Changes (grade 3)
Procedure

Discuss how plants get water to all parts of the plant (via the xylem vessels) and how food moves from the leaves to the rest of the plant (via the phloem).
Do the activities in any order, maybe rotate through stations.

Grades taught
Gr 3

Plant xylem vessels under the microscope

Summary
Use microscopes to view the xylem vessels that transport the water up the plant.
Science topic (2005 curriculum connection)
Life Science: Plant Growth and Changes (grade 3)
Materials
  • Celery that has been in blue food colouring for an hour
  • Razor blade, or sharp blade
  • Microscope
  • Water and dropper
  • Slide and coverslip
Procedure

We will look at the part of the plant that takes the water from the roots to the leaves and the rest of the plant.
See the blue spots in this stem - this stem was sitting in food dye for the last hour and the water moved up the stem and so did the food dye. The dye shows us where the cells are that take the water up the stem.

Make thin-as-possible slices of celery across the stem, to include one or two blue spots per sample.
One slice on a slide.
Add a coverslip.
Add drops of water until there is water under the whole cover slip.
Look at under the lowest magnification of the microscope first, then increase the power to see the xylem vessels in detail.

Draw the cells.

Grades taught
Gr 3