A box with three compartments, each containing 6 wooden tablets. Each set of tablets is of different wood that varies in weight and color.
The weights are light, medium, and heavy.
- Invite the child to the lesson.
- Open the box and with your dominant hand take out one heavy tablet from the left compartment of the box, and place it on the table. Take out one light tablet from the right compartment of the box, and place it on the table, to the right of the heavy tablet.
- Invite the child to take out the remaining heavy and light tablets one at a time, making two stacks, one for light tablets and one for heavy tablets.
- Explain that one stack of tablets are all the same, and that the other stack of tablets are all the same, but that the two stacks are different from each other.
- Pick up a heavy tablet and let it rest in one hand on your fingertips, only slightly resting in your palm. In the other hand, pick up a light tablet and let is rest in a similar position.
- Make sure your elbows are not touching your body and that you arms are not on the table, gently weigh the two tablets by going up and down with the tablets in your hands. Try it with your eyes closed. Invite the child to do it.
- Repeat this process with two of the same tablets being heavy. Invite the child to do it.
- Repeat this process once more with two tablets that are light. Invite the child to do it.
- Ask the child to watch. Mix up the tablets and place them in two stacks towards the front of the table.
- Put the blindfold on. Pick up a tablet with each hand and weigh them simultaneously, creating one stack in the middle of the table for heavy tablets and another stack for light tablets. Repeat this process until all tablets are sorted into the two stacks in the middle of the table.
- Once you’re done, remove your blindfold. Check your work and invite the child to randomize the tablets so that he can perform the exercise.
Exercise 1, Heavy and Light Tablets
Exercise 2, Heavy and Medium Tablets
Exercise 3, Light and Medium Tablets
Exercise 4, All Three Sets of Tablets
Light, heavy, medium.
Control of Error
Visual confirmation once the blindfold is removed.
Refinement of the baric sense (the sense of weight).
3 1/2 to 4 1/2
Light tablets are 20 grams, medium are 30 grams, and heavy are 40 grams.