How to Determine the Best Length for Your Assessment

There are so many factors to consider when you sit down to write an assessment for your class. A familiar run of questions might pop into your head: What types of questions do I include? What’s the best way to word instructions? And perhaps sometimes one of the biggest and most difficult questions to answer: how long do I make the assessment? When it comes to test length, it’s essential to find that sweet spot that accurately and fairly evaluates students’ understanding without burdening students with too many questions.

We recently looked at data from 400,000 teachers and 3.8 million unique assessments across all grades K-12 and subject types to determine the average length for various digital assessments. The data we looked at is based on assessments that were completed by five or more students. Overall, teachers seem to keep assessments to an average of 11.4 questions for elementary school teachers and 15.3 for middle and high schoolers. Below is a breakdown of the information.

Average Question Count Data

By Subject:

By Grade:

Interesting Trends: 

Overall: 

• The average number of questions seems to vary more across subject rather than across single grades

By Subject:

• Social Studies has the highest average amount of questions (18.2) while ELA has the least (11.4)

By Grade: 

• The average number of test questions generally rises with older grades
• The average number of test questions for elementary schoolers across grades is 11.4. Across individual grades, there is relatively little variation from this number.
• The average number of test questions for middle schoolers is 14.366
• The average number of test questions for high schoolers is 15.975.

An Important Factor to Consider for Test Length: Time

Of course, the best length for your test also depends on other factors besides just your class’ grade and subject. The biggest factor to consider is the time constraint your students are under. According to Carnegie Mellon University, “When students are under time pressure, they may make mistakes that have nothing to do with the extent of their learning.” Therefore, it’s important that you allot an appropriate amount of time for your assessment.

Generally, when determining how long to make your assessment, the Eberly Center of Testing Excellence at Carnegie Mellon University recommends that you time yourself taking your exam and then triple that time for students. If you want a fresh set of eyes to look at your exam, you can also give it to a TA (if you have one) or a teacher friend to take, and then anywhere from double to quadruple the time they take for your students depending on your subject and grade level.

How much time you should allot for your exam also depends on the types of questions on it. Kansas Curriculum Center’s David Clay suggests: 

• 30 seconds per true-false item
• 60 seconds per multiple choice item
• 120 seconds per short answer item
• 10-15 minutes per essay question
• 5 to 10 minutes to review the work

Another Important Factor to Consider for Test Length: The Purpose of the Assessment

The length you make your test should also depend on the purpose of your assessment. Formative assessments, which are designed to evaluate and correct student misconceptions while learning, should be shorter so they can be more frequent and thus keep up with student progress more effectively. Meanwhile, summative assessments, which evaluate learning at the end of an instructional period, tend to be longer since they summarize learning and are less frequent. Bell ringers and exit/entry tickets might be a short 1 to three questions long, as they serve as a quick check for comprehension. Finally, end of year assessments might be the greatest length of them all as they are often intended to evaluate student comprehension of concepts learned throughout the entire year or semester. Read more in our blog post about types of assessments.

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