Home >COMM-Subjects >Visual Communication >Data Visualization >Teaching Data Visualization >Data Visualization Assignments >Pie Chart Redesign Challenge

Pie charts are among the most recognizable forms of data visualization. They are commonly used in presentations, news graphics, marketing reports, and dashboards to illustrate proportions or parts of a whole. Because they appear simple and familiar, pie charts are often used without careful design consideration.

However, poorly designed pie charts can confuse audiences, exaggerate differences, and make accurate comparisons difficult. Labels may overlap, slices may be difficult to distinguish, and unnecessary visual effects—such as 3D formatting—can distort perception.

This Pie Chart Redesign Challenge assignment asks students to critique and improve a poorly constructed pie chart. Instead of simply creating a chart from scratch, students will analyze an existing visualization, identify its weaknesses, and redesign it using clear data visualization principles.

By completing this assignment, students will develop critical thinking skills about chart design and learn how small visual decisions can significantly affect audience understanding.

Why This Data Visualization Assignment Matters

Pie charts are intended to communicate proportions within a whole. When designed correctly, they can quickly show how categories contribute to a total. However, pie charts are often misused or poorly formatted.

Common problems with pie charts include:

Too many slices that make comparison difficult
Labels that are crowded or unclear
Similar colors that make slices hard to distinguish
Decorative 3D effects that distort perception
Unnecessary legends that require constant cross-referencing

Because pie charts rely on visual comparison of angles and areas, poor design can easily obscure important relationships in the data.

Learning how to critique and redesign weak visualizations helps students develop stronger design judgment. This assignment encourages students to think critically about the strengths and limitations of pie charts and apply best practices when revising them.

Learning Outcomes

By completing this assignment, students will be able to:

Identify common design problems in pie charts
Evaluate how visual formatting affects audience interpretation
Apply best practices for presenting proportional data
Redesign charts to improve clarity and readability
Use color and labeling strategically
Explain visualization improvements using clear reasoning
Demonstrate ethical awareness in visual data presentation

Assignment Overview

In this project, students will begin with a poorly designed pie chart provided by the instructor or found in a real-world source such as a news article, marketing report, or infographic. Students will analyze the chart, identify its weaknesses, and redesign it to communicate the same data more clearly.

The assignment focuses on:

Visualization critique
Design revision
Audience-focused communication
Ethical presentation of proportional data

This assignment works well in:

Introductory data visualization courses
Communication and journalism classes
Business analytics courses
Research methods courses
Technical writing courses
Information design courses

Students may use data visualization tools such as:

Excel
Google Sheets
Tableau
Power BI
Canva
R or Python

The emphasis is on thoughtful redesign rather than technical complexity.

Deliverables

Students will submit:

The original pie chart being evaluated
A redesigned version of the chart
A written explanation of the design improvements made
A clearly formatted submission file containing the visuals and written analysis

Each redesigned chart must include:

A clear and descriptive title
Distinct and readable slices
Logical ordering of categories when possible
Legible labels or annotations
Consistent color use
Minimal chart clutter

The goal is to create a chart that communicates proportions clearly and efficiently.

Step-by-Step Instructions for Students

Step One: Examine the Original Pie Chart

Begin by carefully reviewing the provided or selected pie chart.

Observe the chart and identify potential design issues. Consider questions such as:

Are there too many slices to easily compare?
Are labels readable and clearly associated with slices?
Are colors distinct enough to differentiate categories?
Does the chart include unnecessary visual effects?
Is the title clear and descriptive?

Take notes on the strengths and weaknesses of the original visualization.

Your goal is to identify how the chart’s design affects interpretation.

Step Two: Identify Specific Design Problems

Create a short list of the design problems you observe.

Examples may include:

Excessive number of slices
Similar colors that make categories difficult to distinguish
Labels that overlap or clutter the chart
Use of a legend instead of direct labeling
3D effects that distort slice size
Poor ordering of categories

Focus on problems that reduce clarity, accuracy, or readability.

Step Three: Reconstruct the Data

If the original chart does not provide raw values, estimate the data values from the chart or locate the underlying dataset if available.

Recreate the dataset in your visualization tool so that you can redesign the chart from scratch.

This step ensures that your redesign represents the same information as the original visualization.

Step Four: Design a Clearer Pie Chart

Create a redesigned version of the pie chart using best practices.

Focus on improvements such as:

Limiting the number of slices
Using distinct colors that improve contrast
Removing unnecessary decorative elements
Placing labels directly near slices when possible
Organizing slices logically (such as largest to smallest)

Ensure that the redesigned chart accurately reflects the data while improving clarity.

Step Five: Evaluate Whether a Pie Chart Is Still the Best Choice

While redesigning the chart, consider whether a pie chart is the most effective visualization for the data.

In some cases, a bar chart may communicate comparisons more clearly.

Even if you retain the pie chart format, briefly explain why the chosen visualization works—or where its limitations remain.

Step Six: Write a Redesign Explanation

In the written portion of the assignment, explain:

What problems existed in the original chart
What changes you made in the redesign
How the new design improves clarity and interpretation
What audience the revised chart is intended for

Your explanation should focus on design reasoning rather than simply describing the chart.

Assessment Criteria

This data visualization assignment will be evaluated based on the following criteria:

Critical Evaluation

Clear identification of problems in the original chart
Thoughtful analysis of design weaknesses

Redesign Quality

Improved clarity and readability
Effective use of color and labeling
Removal of misleading or distracting elements

Analytical Explanation

Clear explanation of design improvements
Evidence of visualization reasoning
Awareness of audience interpretation

Professional Presentation

Organized layout of visuals and text
Legible chart formatting
Polished writing and explanation

Strong submissions demonstrate both critical evaluation and thoughtful design improvement.

Common Student Mistakes to Avoid

Students sometimes encounter the following issues when redesigning pie charts:

Keeping too many slices in the chart
Using similar colors that reduce clarity
Leaving labels ambiguous or crowded
Failing to remove unnecessary decorative effects
Ignoring the limitations of pie charts for detailed comparison

Remember that good redesigns prioritize clarity and simplicity.

Related Assignments

Continue developing your data visualization skills with these related projects:

These assignments expand your understanding of visualization design, critical analysis, and effective communication of data.

*Content on this page was curated and edited by expert humans with the creative assistance of AI.