A School of Continuous Improvement research poster reconstructs a decade of tooth fairy payouts across 214 households, finding a rate set by sibling precedent, quantised to the coin drawer, and repriced only by playground news.
A decade of payout histories across 214 households finds the pillow's going rate set by sibling precedent and moved only by playground news
Who Sets the Tooth Fairy’s Rate?, a research poster released today by the School of Continuous Improvement, treats the coin under the pillow as a question in monetary economics, and finds a price stickier than most of the prices the discipline usually studies.
Across 214 households and 1,838 recorded pillow visits, the research team reconstructed a decade of payout histories, cross-checked against coin jars and banking records. The going rate, they report, holds for a median of 4.8 years, never moves downward, and steps upward almost exclusively to the next coin or note the bedside drawer can supply. Most repricings follow within days of a richer pillow being mentioned at the school gate or in the class chat.
A price like this is less a decision than an inheritance. Households knew their number the way you know a birthday: nobody could tell us where it came from, and nobody wanted to be the one to change it.
— Dr Joost Nwosu, Postdoctoral Fellow, School of Continuous Improvement
The poster brings the payout ledger, an eighteen-month household diary and the school-gate grapevine into a single account of how the rate travels: anchored by what an older sibling was once paid, quantised by the drawer, and moved only by outside news. For the School, the work marks a deliberate widening of its evaluation-ecosystem agenda into the smallest ledger a family keeps.
A district parents’ association has since adopted the study’s median as the suggested rate in its kinder handbook, indexed annually. “When a suggested rate meets its first indexation round, we will learn something about who the suggestion was for,” said Dr Mirela Hanke, Postdoctoral Fellow.
The full poster is available from the University’s research repository under an open licence, doi:10.5555/slop.06kohn.