Mean and median in programming data are the focus of this Grade 9 Computer Science worksheet, helping students calculate measures of center, compare how they behave, and connect statistics to programming-style thinking with variables and lists. Students also examine how outliers can affect the mean and why the median may sometimes better represent a typical value. :contentReference[oaicite:0]{index=0}

Connect statistics with data processing

The lesson introduces mean as the result of adding all values and dividing by the number of values. Median is presented as the middle value after a data set has been ordered, with students also considering what happens when there is an even number of values.

Students then compare the two measures using data sets that include outliers. Because the mean uses every value in its calculation, an extreme value can pull it away from the rest of the data. The median depends on position instead, making it less affected by extreme values in many cases.

Skills students practice

• Calculate the mean of a numerical data set
• Find the median after ordering values correctly
• Compare mean and median when an outlier is present
• Explain which measure better represents a data set in context
• Describe how variables, lists, sorting, and calculations can be used in code

From calculation to programming-style reasoning

A dialogue, matching activity, cloze passage, labeled diagram, and reading passage introduce the key concepts. Multiple-choice and true-or-false questions ask students to calculate means and medians, identify incorrect methods, and reason about the effects of outliers. Short-answer prompts require students to explain the difference between the two measures and describe how the median is found for an even-sized ordered list.

The extended response connects the statistics directly to programming. Students analyze a program that sorts a list and returns the middle value, explain that it is computing the median, and discuss when calculating the mean would be more appropriate.

Teacher support included

A separate teacher guide PDF includes learning objectives, teaching tips, discussion questions, and common mistakes. Use this mean and median worksheet during a Data and Information unit, when connecting mathematics with programming concepts, or as review before students work with larger datasets. The resource helps students move beyond formulas by asking them to interpret which measure best represents the data.