What is the marshmallow test?
The marshmallow test gives a young child a choice: eat one treat now, or wait and get two. It measures delay of gratification, the ability to resist an immediate reward for a larger later one. Psychologist Walter Mischel and his team ran these studies with preschoolers at Stanford’s Bing Nursery School in the 1960s and 1970s.
- Researchers
- Walter Mischel and colleagues
- When
- 1960s–1970s
- Participants
- 4- and 5-year-olds at a Stanford preschool
- Measure
- How long children waited for the larger reward
How the experiment works
- A marshmallow (or another treat) is placed in front of the child.
- The researcher says, "If you wait until I come back, you can have two," and leaves the room.
- The child can ring a bell to call the researcher back at any time but then gets only one.
- Researchers record how long the child waits.
The original findings
The famous claim was that preschoolers who waited longer did better as teenagers. In Mischel’s follow-ups, children who waited longer tended to be rated by parents as more academically and socially competent in adolescence and had higher SAT scores.
Arguably the more important finding was about strategies. Children who stared at the treat gave in quickly, while those who covered their eyes, sang songs, or imagined the marshmallow as a fluffy cloud waited much longer. Self-control, in other words, is partly a learnable skill rather than raw willpower.
The 2018 replication and criticisms
The original samples were small and drawn largely from the children of Stanford faculty and students. Watts, Duncan and Quan (2018) revisited the question with data on more than 900 children from a more diverse US sample.
| Aspect | Original studies | 2018 replication |
|---|---|---|
| Sample | Small, Stanford preschool | Larger, diverse US families |
| Link between waiting and age-15 achievement | Relatively strong | About half as large |
| After controlling for family background and early cognitive ability | – | Much smaller |
The story shifted from "patient kids succeed" to a picture in which family economic stability and home environment shape both the ability to wait and later achievement. Other research found that children wait less when the adult has proven unreliable, suggesting that taking the treat now can be a rational choice in an unpredictable world.
Helping children build self-control
- Teach waiting strategies. Practice looking away and shifting attention to something else.
- Keep promises. Children learn that waiting is worth it when adults follow through.
- Break goals into steps. Make the path to a bigger reward visible.
- Let them choose. Self-chosen goals are easier to sustain; see self-determination theory.
Frequently asked questions
- What is the marshmallow test?
- It is Walter Mischel’s experiment in which a child chooses between one treat now or two after waiting, used to study delay of gratification.
- Do kids who wait longer become more successful?
- The original studies found a link, but a 2018 replication found it was about half as strong and shrank substantially once family background was taken into account.
- How can I help my child wait longer?
- Teach distraction strategies such as looking away or thinking about something else, and build trust by keeping your promises.
References
- Mischel, W., Shoda, Y., & Rodriguez, M. L. (1989). Delay of gratification in children. Science, 244(4907), 933–938.
- Shoda, Y., Mischel, W., & Peake, P. K. (1990). Predicting adolescent cognitive and self-regulatory competencies from preschool delay of gratification. Developmental Psychology, 26(6), 978–986.
- Kidd, C., Palmeri, H., & Aslin, R. N. (2013). Rational snacking: Young children’s decision-making on the marshmallow task is moderated by beliefs about environmental reliability. Cognition, 126(1), 109–114.
- Watts, T. W., Duncan, G. J., & Quan, H. (2018). Revisiting the marshmallow test: A conceptual replication investigating links between early delay of gratification and later outcomes. Psychological Science, 29(7), 1159–1177.