Numbas

Numbas is a free open-source assessment tool that performs automatic marking on a variety of answers, including mathematical expressions, numbers, boolean operations, short text and multiple-choice. It provides a straightforward way to create online tests for mathematical subjects and other numerate disciplines. Numbas allows for randomisation of the given values in a question, so each student can see different variables but experience the same level of difficulty.

Questions and tests created in Numbas can be downloaded and then imported to Blackboard in self-contained assessment packages. The integration with Blackboard allows instructors to set up multiple tests and track students’ scores and progress.

Numbas offers the option of collaborating with other authors, giving them the chance to contribute to the pool of questions and use the ones already available. In addition to the collaborative area where instructors can download original questions, Numbas has a public database containing thousands of ready-made questions that are accessible to their users.

Numbas can be used for formative and diagnostic purposes e.g. weekly tests or practice materials. Currently Numbas is not recommended for summative assessment.

Advantages

1. Collaborative space to create and download questions.
2. All questions created are private by default unless published.
3. Public database with questions and tests.
4. Questions include variable values, text and diagrams, so each student sees a different version of the question but experiences the same level of difficulty.
5. Students can get instant feedback on their answers including a worked solution.
6. Integrated with Blackboard and student marks are available in the Grade Centre.

How it works

There are three steps to set up a Numbas test:

1. Sign up for a free Numbas account. There is comprehensive support documentation to help you set up your account.
2. Learn how to create new questions or use the available public content to build your test. Then download your test as a package from the Numbas website.
3. In the relevant section of your Blackboard course, create a Numbas item (from the ‘Build Content’ menu) i eg Assessment, submission and feedback. Ensure you tick ‘enable evaluation’ and import the Numbas package you previously downloaded.

Students can then take the test via Blackboard and see their marks/ feedback in the Grade Centre. Instructors are able to check student performance in the Grade Centre as well as on the Numbas dashboard in Blackboard.

For more information about setting up a Numbas test in Blackboard please refer to our Staff guide on how to.

Getting further help

If you have questions about using Numbas, the Numbas users mailing list is a good place to ask for help. If you would like to join the University of Bristol Numbas user community (on Teams), or have any other queries, including questions regarding Blackboard integration, please contact: digital-education@bristol.ac.uk.

Accessibility in Numbas

Numbas editing and exams interfaces aim to meet WCAG 2.1 AA level accessibility standards. However, there are some limitations to keep in mind when using the editing interface:

• The colour contrast on some button labels does not meet WCAG AA level standards.
• There has been little testing done with screen readers; navigating the interface can be cumbersome and parts of the interface that update in response to actions are not automatically read out by the screen reader.
• The editor interface is not very easy to use on narrow screens such as mobile devices.

Although, the accessibility statement for Numbas exams does not report any known limitations, it may be useful to keep in mind that:

• The document has not been updated since 2019.
• Mathematical notation requires the installation of additional software.