Cards for coloured cylinders

MATERIAL OVERVIEW:

• 1 red box containing ten red cylinders whose diameter varies by 5 mm while the height stays constant: 5.5 cm. (variation in two dimensions)
• 1 yellow box containing ten yellow cylinders whose diameter and height vary by 5 mm: 1 cm tall for the largest cylinder and 5.5 for the thinnest one (variation in three dimensions)
• 1 green box containing ten green cylinders graded in the opposite way to the yellow ones (variation in three dimensions)
• 1 blue box containing ten blue cylinders whose height varies while each cylinder keeps the same diameter (variation in one dimension)
• 2 mirrors

Example of a practical exercise:

With the red, yellow and green boxes:

1. Go to the shelf with the child
2. Sit down at a table and name the activity: "These are the colored cylinders, and what color are these ones?"
3. Remove the lid and place it under the box
4. Slowly take out all the cylinders one by one, close the box and set it aside
5. Take the largest cylinder and place it on our left
6. Each time choose the thickest cylinder among those left on the table and continue the gradation from thickest to thinnest, lining up each cylinder next to the previous one
7. Once it is done, look at the child and invite them to do it; to do so, mix the cylinders up again
8. When the child has finished the gradation, ask them to fetch another box, the yellow or the green one (not the blue one)
9. Open the lid of the yellow box, place it underneath and take out all the cylinders one by one, arranging them randomly on the table
10. Close the box and set it aside
11. Make the gradation with the red cylinders, then place the yellow gradation alongside the red one
12. Invite the child to look at each side of the gradation, then suggest they do it in turn
13. Mix all the cylinders up again and, once the child has completed both gradations by placing the cylinders on top of one another, take the two mirrors and place one at each end of the gradation. Ask them what they see (the cylinders to infinity)
14. Invite the child to fetch the green box
15. Arrange the yellow gradation next to the red one and invite the child to make the gradation with the green cylinders
16. Place a mirror on each side and look
17. Invite the child to do the same

With the blue box:

1. Take the cylinders out of the box and make the gradation, again from thickest to thinnest
2. Invite the child to do it.