A number that represents the "center" or "trend" of a set of data. The mean, median, and mode are statistical measures of central tendency.
A measure of central tendency is a single value that summarizes a whole set of data by describing where the middle or most typical value lies. Rather than listing every data point, we use one representative number to describe the overall trend.
There are three main measures of central tendency:
-
The mean is the average. Add all the values and divide by how many there are.
-
The median is the middle value when all data points are arranged in order.
-
The mode is the value that appears most often in the data set.
For example, consider the data set: 4, 6, 6, 7, 10, 11, 12.
-
Mean: (4 + 6 + 6 + 7 + 10 + 11 + 12) ÷ 7 = 56 ÷ 7 = 8
-
Median: 7 (the middle value)
-
Mode: 6 (appears twice, more than any other value)
Each measure tells us something slightly different about the data. Choosing the right one depends on what we want to understand, and sometimes, comparing all three gives us the clearest picture.
When Do Students Learn About Measures of Central Tendency?
Students begin building toward this concept as soon as they start organizing and interpreting data.
Grades 3–5 – Introducing Mean, Median, and Mode
Students learn to calculate and interpret the mean, median, and mode for simple data sets, developing their first tools for summarizing information.
Grades 6–8 – Choosing and Comparing Measures
Students deepen their understanding of all three measures, learn when each is most appropriate, and begin connecting central tendency to broader statistical reasoning.
Grades 9+ – Central Tendency in Statistics
Students apply measures of central tendency in more complex statistical contexts, including data distributions, variability, and real-world data analysis.
