Case study: Peer-assessment within group projects


Students participate in group-work, where they have the opportunity to act as both the presenting group and an expert panel to further the discussion with another presenting group. The presentation and expert panel are graded by 2 members of staff and the students then engage in peer-marking. The students are asked to grade the contribution of their teammates, which directly impacts on their teammates’ grades. The students’ individual grade is in proportion to their contribution to the group, encouraging them to contribute more and reflect on their own work.

Key points

College: College of Medical, Veterinary and Life Sciences Sciences
Class size: Extra-large (> 301)
Technological competency: Moderate (Requires some specialised knowledge, but otherwise accessible)
Administrative support: General
Suitable for online/distance learning: No
Corresponding contact: Chris Finlay, Mary McVey, Ian Reid

Course details

Course title: Life Science
Level: Level 1
Module title: Biology 1A and 1B
College: College of Medical, Veterinary and Life Sciences Sciences
Instructor: Chris Finlay
Implemented since: 2009

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All of the assessments for the course are managed electronically. This was the result of a move away from paper hand-ins, which was a heavy administrative load considering the large class size. Moodle is used to manage the majority of this.
Students often feel that their work is under-represented during group projects, and this approach aims to address that disparity. The highest grade that each student in the group is able to get is that of the staff grade. Each students individual grade is calculated from the peer scores awarded by their team mates in relation to the staff score.

This form of assessment encourages students to:

  • think about their contribution towards their group project
  • critically assess other students’ work
  • think about the type of criteria used in assessment and construct their own

Implementation (what was done)

  • The students participate in two group projects in year 1, one in Biology 1A and the second in Biology 1B. Each project is worth 15% of the overall grade.
  • Within each course, the students are put into groups of 8-9 students and are given 5-6 weeks to work on their group project. Each group is given a task - in the first semester it is a 5 minute presentation on invasive species. In the second semester the students have to create a poster presentation on a current area of research. In both instances they have to also act as an expert panel for one of the other groups.
  • The students are given a forum on Moodle which only their team-mates and staff can access. The forum acts as the evidence for how much each individual team-member contributes to the project.
  • At the start of the group project each group has to discuss and agree 4 marking criteria that they will use to peer score each other. These criteria will vary from group to group as they identify their own priorities.
  • On the day the groups present they are assigned two staff markers. Using a marking scheme that has been available to students throughout the entire project, the two members of staff agree on a grade between themselves. This is the grade is for the group.
  • To determine the individual grade, the student group peer-score each other. The students submit their peer scores via a webform that is unique to each student. The student can access the form, and see the names of all their group members and the marking criteria they chose at the start of the year.
  • They then score each member of their group against the criteria from 0-5 (0-didn’t do anything, 5-excellent). The top-scoring students in the group get awarded the ‘staff score’ (the score determined by the two members of staff); this is the maximum score. If the group all score each other equally, everyone gets the staff score. If a group-member gets a low score, they receive a lower individual score than the ‘staff score’.
  • The students get feedback on both their presentations and their role as expert panel.

Considerations (and what worked well)

  • The maximum grade that the students are awarded is the ‘staff grade’. The peer scores are mapped back to this staff grade so no student in a group can be awarded more than the staff grade.
  • Even though the students are able to select their own marking criteria, they typically identify similar criteria. This facilitates comparison between the groups.
  • The peer score is also checked for unusual grading patterns before it is released as part of the moderation process. The staff look for large discrepancies that might flag up issues with the peer scoring and account for these using a set of specific rules.
  • Every year, a small percentage, typically 1% of the class, query their grade. This is remarkably low for a class of around 600-800.
  • A formula is used to work out the grade-reduction based on the peer-score. The peer-grade is mapped to the 22 point scale, and the student is awarded a specific grade based on their peer evaluation.
  • To give students the ability to query their scores, a method for gathering evidence has to be provided. Students are all given access to group Moodle forums, and these are used as evidence. The students are reminded that this is the only evidence that will be accepted (e.g. Facebook groups cannot act as evidence).
  • The peer-scores are anonymous, so that the students see their final peer scores, but they don’t see who gave them what.

Scalability and Transferability

Approach would work on different class sizes.

Approach would be transferable if the resources are available.


Student benefits 
  • Students have access to the marking rubric for their presentation from the start of the semester, so they will know what they are being graded on.
  • Students have access to feedback from a variety of sources (staff panel, expert panel, group).
  • If taking Biology 1A and 1B, students go through the group-work process twice, and gain confidence in the assessment style.
  • Students feel that the amount of work they do is rewarded.
Staff benefits 
  • Staff are able to use the marking rubric for grading the presentation.


Student challenges 
  • Students have to use Moodle to communicate with their group, instead of social media, which they might be more familiar with.
Staff challenges 
  • A lot of administrative work is required in setting up a webform for the students’ marking criteria.
  • The moderation process can be time-consuming.

Supporting material


Cogdell, B., Finlay, C., and McVey, M. (2011) Peer-assessment of group work in a large class: development of a staff and student friendly system. In: Orsmond, P. (ed.) Self- and Peer-Assessment: Guidance on Practice in the Biosciences. Series: Teaching Bioscience: Enhancing Learning Series. The Higher Education Academy, UK Centre for Bioscience,: Leeds, pp. 49-51.