ingridscience

Students add a spoon of soil to a tube, then fill the tube 3/4 of the way up with water. Shake, then let it settle.
A few seconds of settling gives some instant generalized results, and settling over a longer time gives more detailed results.

Organic matter/dead living things float.
Tiny clay particles ('mineral' component) are suspended in the water column.
Heavier sand and gravel particles ('mineral' components) sink to the bottom of the tube or jar.

Discuss the relative amounts of different components in the different soil types.
For the soil types we tested:
forest soil is almost all organic
beach soil is a mix of organic and mineral components although by volume the mineral component is larger
garden soil is a mix of organic and mineral components, with a lot of tiny mineral particles suspended in the water.

If this activity is done in a larger mason or jam jar, and left to settle over days, the mineral layers of clay, sand and gravel separate out more clearly, and their relative heights can be measured for an accurate breakdown of the mineral (rock) components of the soil.
See the image at https://images.squarespace-cdn.com/content/v1/5cdecce138275f0001d2fd9b/…
and "Soil texture jar test' at https://bcfarmsandfood.com/three-simple-ways-test-soil/

Students work in groups, ideally 4 students or less, each group with a set of sieves, and one or more soil samples.

If using one sieve, the students can separate the large and small components:
Scoop a small amount of soil into the sieve. Shake the sieve over a clean tray so that the small components fall into the tray and the large components remain in the sieve. The separated components make it easier to study what the soil is made up of.

If using a series of different mesh sizes the students can do several separations of components:
Dump the soil onto the large mesh sieve laid over a tray. Shake the sieve and tray simultaneously until soil stops falling through the sieve. Transfer the large soil components trapped by the sieve onto a sheet of white paper. Dump the contents of the tray onto the next smallest sieve size (sitting on a tray), repeat the shaking, transfer the trapped components to a new white sheet of paper. Repeat for the smallest sieve size. Transfer the soil remaining in the tray after the third and final sieve to its own sheet of paper.

Clean the sieves then repeat the soil component separation for the other soil types.
For each of the soil types, lay the separated components side by side to show the change in the soil components between soil types and from large to small.

Play-Debrief-Replay format:
This activity was run in a free-experimentation lesson using two soil types and one sieve size. Students were allowed to explore as they liked (though were requested to keep the soil types separate and in the trays). They took notes on what they found. We gathered as a class and heard what the students had found. Then students chose a particular aspect of the activity that they wanted to pursue further, then returned to the materials to investigate this further, partnered with students that had a similar interest.

Thank you Exploratorium for this activity: https://tinkering.exploratorium.edu/sites/default/files/Instructions/sc… and https://tinkering.exploratorium.edu/scribbling-machines

For drawing jiggly lines: (photos 1-4)
Tape some pieces of popsicle stick together, or cut a piece of glue stick. Popsicle sticks need to be taped firmly after pushing the motor shaft through them. For the glue stick, use a skewer to make a hole in it, then push it onto the shaft. Other weights can be used too, but make sure they are attached firmly. The lop-sided added weight will "offset" the motor and make it shake.
Tape the offset motor on a top edge of the plastic tub, so that when it spins the added weight does not hit the tub.
Tape the battery to the top of the tub, and attach the motor wires so that one of them is easily removable with a flap of tape (see close up photo).
Tape three marker pens as legs to the tub.
Start the motor and place the scribbling machine on the paper.

For drawing smooth circles: (photos 5-7)
Tape the motor to the plastic tub so that its shaft is pointing down, making one leg.
Tape two marker pens around the tub to make two other legs.
Tape the battery to the top of the tub, then connect it to the motor with masking tape.
Start the motor and place the circle-drawing machine on the paper. The marker pens may need to be moved around a bit until it is stable.

Students find the flowers in the images, count the number of petals on several of the flowers (e.g. 5), and record the numbers.
Students can add their numbers to a class chart, to see how there is a common number of petals for each type of flower, but there is also some variability.

While the popcorn starts popping, show students slow motion videos of popcorn kernel popping:
https://www.youtube.com/watch?v=NCSr18vtjeo
https://www.youtube.com/watch?v=CXDstfD9eJ0
Talk about what is happening in the kernels:

Each kernel has some water in it. (Corn that is used for popcorn has just the right amount of water: 13.5%.) As the hot oil heats up the kernal, the water inside it evaporates to form a gas (water vapour). The shell is strong and watertight so the gas cannot escape.
As the heat increases further, the water vapour molecules move around more and more vigorously, exerting more and more pressure on the inside of the shell. Eventually the pressure inside the kernel is great enough to burst the shell. (This happens at about 180 centigrade, when the pressure inside is 135psi.)
As the shell bursts the pressure suddenly drops again. This causes the water vapour to expand which makes the starch and proteins inside the kernel expand into an airy foam.

Students can inspect the kernels as they eat them, and see that the shell turns inside out from the force of the explosion.

If students have done some acting out the sates of matter already, they can do skits in small groups on what is happening inside the popcorn to make it pop - each student can be a water molecule, or the kernel shell, or a narrator. Gather to view each others' skits.
(Students can prepare their skits as the popcorn pops if it takes a while.)

Make popcorn with a microwave and paper bag; https://www.allrecipes.com/recipe/87305/microwave-popcorn/
Note that cooking too long will burn some of the already popped kernels, so go under time if anything.

Corn kernel molecules and popping explanation link: https://www.acs.org/content/dam/acsorg/education/whatischemistry/advent….
More popcorn info at: https://www.popcorn.org/All-About-Popcorn/What-Makes-Popcorn-Pop
Scientific paper on popcorn popping: https://royalsocietypublishing.org/doi/10.1098/rsif.2014.1247#:~:text=W….

For a lesson on heat:
Popcorn can be made as part of a lesson on heat. Students brainstorm whether the popcorn is being popped as a result of conduction, convection, radiation or all of them.

For a lesson on seeds:
Compare popcorn kernels with the kernels on a corn cob.