Recurring School Accidents
Uncovering the Hidden Dangers in Places of Learning
By Akiha Komatsu | August 2025
This article is based on data from the Japan Sport Council.
There are children who have died or been left with lasting disabilities due to accidents at school.
1,151 children died, and 7,682 children suffered some form of disability
According to the accident data published by the Japan Sport Council since 2005, many children have experienced accidents at school, which is supposed to be a safe place.
The number of children who die or are disabled in school accidents has been on a declining trend, but nearly 400 children still suffer such outcomes each year.
Number of Accidents by Category
To better understand the data, accidents were categorized into five groups: Commuting, Class & Break Time, Club Activities, School Events, and Others.
*Accidents during childcare or swimming instruction are included under "Class & Break Time" even during summer break.
Accidents During Class & Break Time
Let's look closer at "Class & Break Time", which accounts for 48% of all school accidents.
To understand patterns in fatal accidents, we used clustering to group cases based on similar causes, locations, and circumstances. As a result, several similar clusters emerged.
For example, one cluster includes keywords like "School lunch", "Choking", "Children".
In multiple cases, children choked to death on food items like bread, edamame, and quail eggs.
*Some keywords remain in Japanese because the original analysis was conducted in Japanese.
Another cluster shows keywords like "PE class", "Heart", "Endurance (Run)".
According to the Japan Sport Council, at least 35 students died from sudden cardiac arrest during PE classes between 2005 and 2023.
Keywords indicating strenuous activity like "Running" and warning signs like "Suddenly" and "Collapse" repeatedly appear not only in PE but also in "Club Activities" and "School Events" clusters.
What We Learn from Recurring Accidents
The analysis reveals that some accidents tend to recur in similar situations.
Choking during lunch and cardiac arrest during PE class may seem random, but they follow recognizable patterns.
These insights suggest the need to rethink daily risks and create systems to prevent future accidents.
About the Data
The data on school accidents was obtained from the Japan Sport Council's Injury and Accident Mutual Aid Benefit System .
We analyzed fatal case reports submitted between fiscal years 2005 and 2023 using morphological analysis, clustering, and network analysis.
The analysis was conducted using Python (pandas, fugashi, scikit-learn), and visualized with D3.js and Observable.