Collect whole dandelion seed heads with their stalks attached. You will need at least one for each pair of students, plus some spares. Very gently place them in a container without tangling them, put the lid on and take back to class.
What You Will Need:
Mature dandelion seed heads.
HB, B or 2B grade grey pencils.
Small yoghurt pottles.
What to do
Drawing the seed head
Place a seed head upright in a pottle that is half full of water. Make sure the head itself is above the lip of the pottle. The seed head doesn't need to be complete, and can be used by two students.
Use an ordinary grey pencil for your drawing. First, lightly sketch the shape of the stalk and seed head. If needed, use an eraser for corrections. Good science drawings have simple clean lines and don't use shading.
Take turns to kindly help your partner by critiquing their drawing, saying what specific parts are good, and giving suggestions about making any parts more accurate.
Once you have made changes and you think the shape is right, lightly fill in the detail of the whole head. It may be helpful to repeat the critiquing process again.
Finally, make your lines cleaner and firmer. Label your drawing.
Drawing the parachute seed
Use tweezers or your fingers to carefully pluck out a single parachute seed.
Inspect its details using a magnifying glass. Can you find the seed (the achene), the stalk (the pappus 'beak') and the fluffy parachute (the pappus disc).
Create a drawing, again starting with light lines. Repeat the critiquing process, then once you are happy with the shape, firm in the lines and label.
How does it float on the wind?
What roles do the seed, stalk and the fluffy parachute play in helping this little parachute seed float on the wind? (Hints: What part catches the wind? How does it do this? What part acts as a weight to counterbalance the fluffy parachute? How are the seed and fluffy parachute joined? How far would the seed float in the wind without the fluffy parachute? Use scissors to test it out.)
What use is there to a seed being able to float on the wind?