Recruit children between ages 6 and 9. For the purposes of this demonstration, only one child is tested. Larger sample sizes (as in the Shin, Bjorklund, and Beck study¹) are recommended when conducting any experiments.

Participants should have no history of developmental disorders and have normal hearing and vision.

1. Prepare study materials.

1. Create a set of 18 cards with a black-and-white picture of a common object and the printed name of the object on each card.
   1. An example list of objects is: bicycle, bus, ship, truck, train, taxi, grapes, watermelon, banana, strawberry, cherry, lemon, crocodile, deer, pig, bear, squirrel, and zebra.
2. Create and print a number line showing the numbers 1-18.

2. Data collection

1. Memory estimation
   1. Sit the child on the opposite side of the table as the experimenter.
   2. Explain that the child is going to be playing a memory game. Tell the child, “I am going to show you 18 pictures. You will have two minutes to study them any way you like.”
   3. Ask the child, “How many of the 18 pictures do you think you will remember?” and show the child the number line.
   4. Record the child’s response. 
2. Picture presentation
   1. Present the child with each of the 18 cards one at a time.
   2. When presenting each card, ask the child to name the object on the card or read the label. Correct any errors.
   3. After the child has named the picture, place the card face up on the table. 
3. Study
   1. When all 18 cards have been presented and are on the table, tell the child that they will have two minutes to study the cards.
   2. Set a timer for 2 min.
   3. Allow the child to study the cards in any way they see fit.
   4. Notify the child when time is up, then pick up and put away the cards. 
4. Delay
   1. The goal of this portion of the procedure is to create a buffer between study and test, in order to ensure that the child is not continuing to rehearse the studied items.
   2. Give the child a set of puzzles or mazes and ask the child to complete them.
   3. Set a timer and allow the child to work on the puzzles or mazes for 5 min. 
5. Memory test
   1. Ask the child to recall as many of the 18 items as possible.
   2. Record the child’s responses.
   3. If the child has not recalled any items for approximately 10 s, ask the child if they remember anymore items.
   4. If the child responds that they do not remember anything else, then encourage them to keep trying to remember any other items.
   5. If the child fails to recall any items for approximately 10 s this time, end the memory test session and thank the child for their participation. 

3. Analysis

1. The dependent variables in this study are the number of objects the child predicted they would remember (0-18) and the total number of objects the child actually recalled during the memory test (0-18).
2. Calculate each child’s prediction accuracy by subtracting the actual number of items recalled from the predicted value. This score can be positive, indicating overestimation, or negative, indicating underestimation.
3. Calculate the percentage of children who overestimate their memory for each age group, and compare these percentages by using a chi-square test.