Exploring the Development of Conservation

Conservation refers to the ability to consider more than one dimension of a situation at a time. For example, college students, who have mastered conservation concepts, clearly understand that, when you pour milk from a tall, thin glass into a shorter, wider one, the quantity of milk does not change simply because its height in the glass does. Children, however, must develop the concept of conservation, a process studied in detail by Jean Piaget. This experiment is designed to demonstrate to you how children of various ages respond to typical conservation exercises.

Experimental Procedure

To do this experiment you will need to enlist a few children as subjects who fall between the ages of 3 and 9. Try to find subjects of various ages, with at least one subject under the age of 4½ and one over the age of 7. You will also need ten marbles, paper clips, or some similar object; two glasses, one of which is tall and thin and one which is short and wide; and a ball of clay, Play-Doh®, or some similar substance.

Experiment 1

Be sure the objects in one row are much more spread out than in the other row.

STEP 2 Record your first subject's age in years and months in the proper column in Table 9-1 below.

STEP 3 Tell your first subject you would like to play a few games with him or her which involve solving some puzzles and answering some questions. Try to enlist the cooperation of the subject.

STEP 4 Ask the subject to count the marbles (or whatever object you have laid out) in each of the rows. The subject should be able to count "5" objects in each row. If the subject cannot count to five, count the objects yourself, out loud, pointing to each one as you count.

STEP 5 Now ask the subject, "Which row, this one" (point to one of the rows) "or this one" (point to the other row) "has more marbles in it?"

STEP 6 Wait for the subject to answer. If the subject says they have the same number, record the fact that this is a conservation response in the "Yes" column under the Marble Task in Table 9-1. If the subject responds that one of the rows has more marbles than the other, record this as a "No" response.

Experiment 2

STEP 1 With the same subject, put the marbles aside and bring out the ball of clay. Shape it into two identical size balls. Let the subject look carefully at the two balls and ask, "Are these two balls the same size?" If the subject says "Yes" continue to Step 2. If the subject says "No" continue working with the balls, adding clay to the smaller one, until the subject agrees they are the same size.

STEP 2 In full view of the subject, flatten out one of the two balls into a pancake.

STEP 3 Ask the subject which of the two balls has more clay in it now.

STEP 4 Wait for the subject to answer. If the subject says they are the same size or they have the same amount, score this as a "Yes" response in Table 9.1. If the subject says there is more clay in one of the balls than the other, score the response as a "No."

Experiment 3

STEP 1 Set the clay aside and bring out the two glasses. Fill the shorter, wider glass about half full of water or milk or pop.

STEP 2 Show the two glasses to the subject. Ask the subject to carefully pour the liquid from the wide glass into the thinner one. (You should probably check beforehand to make sure the second glass will not overflow!)

STEP 3 Ask the subject which of the two glasses had more water (or milk or pop) in it.

STEP 4 If the subject says the amount of liquid did not change, record that as a "Yes" response in Table 9-1 below. If the subject reports that there was more liquid in one glass than the other, record this as a "No" response.

Repeat the experimental procedure with each of the subjects you intend to test.

Analyzing the Results

STEP 1 Reorganize your data and transfer them from Table 9-1 to Table 9-2, being sure to record the data in ascending order according to the age of your subjects.

STEP 2 Count the number of "No" responses given by each subject in the three experiments you conducted. Record this number, which will range from 0 to 3, in the proper column in Table 9-2.

If your subjects responded like those studied by Piaget, those younger than about age 5 or 6 will have some trouble in correctly responding in these three conservation tasks. Did your subjects' responses follow this pattern? Were the older subjects better at these conservation exercises than the younger ones? If they were, you should see an inverse relationship between the subjects' ages and their number of "No" responses. Older subjects, in general, are, according to Piaget, in the stage of Concrete Operations and, thus, have mastered the basics of these conservation tasks. Younger children, still in the Preoperational stage, have not yet acquired the logic necessary to solve these problems. How would Piaget explain the results of these experiments? How would an information-processing theorist explain the results?