Accommodating More Students in Labs: Six Strategies for Further Investigation
Since 2019, the Faculty of Science at Dalhousie University has been the only Faculty with a consistent annual increase in enrolment, averaging 3.35%1. Increases in enrolment occurred despite the pandemic and the Federal cap placed on international student registration. While many ongoing conversations have centred on how best to accommodate the increased number of students in classes, one missing conversation is how to accommodate increased enrolment in laboratory sessions. Within the university-wide Laboratory-based Teaching Community of Practice, a group of instructors met to reflect on and discuss practices we have used, or observed, that support increased laboratory training capacity.
In this post, we would like to share our discussion outcomes by highlighting the different strategies for accommodating increased enrolment in a lab setting, and the pros and cons of each method. Our intention is to provide a head start for further investigation, rather than a detailed instructional guide. In each method, we provide a Faculty member who can be reached for further consultation. Note that this post is meant to serve as a starting point for further investigation; individual instructors should consult with their departments before making substantive changes.
Click on the accordions to explore each strategy:
-
Some laboratory sessions may have student enrolment numbers well under the fire code limit to maximize student-TA and student-instructor interactions. In the event of increased enrolment in a lab, the first thing to consider is to increase the number of students per lab session to reach the fire code limit. This is an easy approach without significantly increasing the workload but is very limited in nature. If there is a single digit increase in enrolment, this may help.
In contrast, if lab enrolment has doubled, we need to entertain alternative approaches. The next option is to increase the number of lab sections in the course. While this method can easily accommodate the increased number of students, it also comes with some realistic challenges, such as a higher workload for the instructional team. Without increasing personnel support, TAs and instructors are facing double, or sometimes triple, the amount of work, leading to burnout, and consequently, reduced teaching effectiveness.
Another challenge for this method is cost: is there room in the budget for increased lab sections? Doubling the number of lab sections means increasing the laboratory budget for covering routine consumables (e.g. test tubes) and services (e.g. access to mass spectrometry facility) and for increased TA hours.
The third challenge is scheduling. The questions to ask are: Do you have a lab space dedicated to your course? Are there any free time slots for your lab space? If your answers are “yes” for both questions, then you can add the additional lab sections into the free time slots. If the lab space is already fully occupied throughout the weekdays, one might have to consider evening labs, which we do not recommend, due to safety concerns. Another option is to consider reducing the number of hours for the lab sessions from three to two hours. However, a catch to this work-around is the reduced contact hours, which will affect students’ laboratory experience; curtail the experiments that could be offered; and may affect the accreditation of some programs.
Faculty contact: Dr. Mark Wall, mark.wall@dal.ca, Department of Chemistry & Dr. Simon de Vet, sdevet@dal.ca, Department of Physics & Atmospheric Science
-
If student enrolment has increased above the capacity of the teaching laboratory space, you may consider alternating laboratory sections. In this method, students are split into two cohorts: A & B. On Week 1, cohort A performs the in-person Wet Lab Session #1, while cohort B prepares for the Wet Lab Session #1. On week 2, cohort A participates in Tutorial #1 to analyze their experimental data from the prior week, while cohort B now performs the Wet Lab Session #1. In the following weeks, the cohorts continue alternating time in the Lab and in Tutorials. The advantage of this method is the ease of accommodating many students in the lab without significantly increasing the workload of the instructional team or the lab costs. The disadvantage is the reduced contact hours in the laboratory, which is a concern for quality of student learning and for accredited programs.
Faculty contact: Debra Grantham, grantham@dal.ca, Department of Biology
-
In this model, the teaching lab is open for extended hours (usually beyond the allotted three hours for a typical lab) and students drop in to do experiments, similar to participating in a research lab. This works best for students in upper-year courses, since they are more familiar with the lab setting, able to work independently, and are generally more confident/competent in the lab than more naive students. To ensure the number of students does not exceed the maximum capacity in the lab, students sign in upon arrival (thus booking their seat) and sign out when they exit. The lab tasks, use of equipment or specimens, and questions for the teaching team are more staggered throughout the session. Completion of tasks is evaluated in lab, usually by a signature provided by a member of the teaching team (a photo of the completed task is later uploaded in their lab assignments for grading). This greatly reduces the amount of post-lab marking and avoids issues with AI use. Students are responsible for cleaning the space and equipment used. Again, this is staggered throughout, so there is no bottleneck at the sinks. This model is in practice by Isabelle Aube in BIOL/MARI 3301.
Students have reported that they like the level of flexibility it gives them from week to week. Those who prepare well usually spend less time in the labs (a plus for most) while other students have reported that this setup allows for extra exploration (that is, “nerding out” a bit longer). It also provides opportunity for doing an extra dissection for bonus marks without the feeling of being rushed.
The disadvantages include: having a fairly “chaotic” lab, at times, so instructors need to be okay with this type of environment; and having to hound students a bit more regarding their responsibilities around cleaning, at least in the beginning. To address the disadvantages, one can tweak the timing of TAs’ shift work so that they overlap with other TAs shifts at the most demanding times. In the latest course offering, an additional TA has alleviated some more of the chaos. The addition of this extra TA did reduce the size of each TA contract by swapping marking hours for more contact hours, with the result that the Course Instructor may end up picking up the extra marking duties. With more consistent funding for lab offerings, this model could be implemented without increasing marking or instructional loads elsewhere in the course.
Faculty Contact: Isabelle Aube, Isabelle.Aube@Dal.Ca, Department of Biology.
-
One of the main reasons for the increased enrolment in the laboratory sessions at Dalhousie is that most of the labs are coupled to the lectures. When we welcome more students into our lectures, we end up shuffling more students into the labs, without considering whether they need the laboratory training. Of course, one can always argue the need for laboratory training for science students; however, we also need to be realistic about what students want to get out of our programs in service to their career goals.
For example, Introduction to Biochemistry (formerly BIOC 2200, still offered at the Truro campus (CHMA2002) was a lecture-and-laboratory combined course two decades ago where all students, regardless of future career goals, were enrolled in the labs. However, twenty years later, the enrolment for that course has quintupled, making it impossible to accommodate all students in the lab sessions. To relieve pressure, the Department of Biochemistry & Molecular Biology uncoupled the lecture and the laboratory into two separate courses: BIOC 2300 and BIOC 2610. Upon uncoupling, BIOC 2300 can now welcome all students who need this course, whether for their Major requirement or for Health Professions Program requirements, while only the Biochemistry & Molecular Biology and Microbiology & Immunology Major and Honours students are required to take BIOC 2610 laboratory training. This same approach of uncoupling the lecture from the laboratory training has also been adopted in the Department of Microbiology & Immunology for the courses MICI 2100 (Lecture) and MICI 2400 (Lab). This model not only alleviates enrolment pressure but also enhances the quality of laboratory instruction by reducing class sizes and allowing for more focused, discipline-specific training The advantage to uncoupling the courses is that students who are not actually interested in the wet-lab experience do not need to take it. One disadvantage is a decrease in the variety of courses that students can fit into their academic schedule when a single course (BIOC 2200) becomes two courses (BIOC 2300 + BIOC 2610) in their 40-course Degree. This flexibility supports students with diverse academic and career goals, including those pursuing professional programs or interdisciplinary degrees
Faculty contact: Dr. Shawn Xiong, shawn.xiong@dal.ca, Department of Biochemistry & Molecular Biology; Dr. Lois Murray, Lois.Murray@Dal.Ca, Department of Microbiology & Immunology
-
Online laboratory offerings may be moving from trend to expectation for Gen Z students. As one student noted, “[f]lexibility has become not just a preference but an expectation.”3 Although on-campus laboratory offerings continue to be constrained by Faculty availability and limited lab space and time, online laboratory options can significantly expand capacity, especially under budget constraints.
For example, when faced with a TA budget cut, the First Year Chemistry Laboratory Team at Dalhousie shifted several experiments online to manage safety training, beginning of term enrollment fluctuations, and the more skills-heavy experiments where students require more support and therefore more TAs. Through this approach, students are now fully safety trained, settled into their classes, and have an opportunity to see how our labs operate, all in an online environment, before entering the in-person laboratory. From a teaching team perspective, class lists are stable when in-person labs begin, and teaching time is distributed to where students need it most. We are strongly of the opinion that an online laboratory is not fully equivalent to an in-person experience, so we re-arranged experiments to ensure that online labs were observation-based and demonstrative of skills that students would soon have the opportunity to practice in-person.
Online laboratory sessions can also be used when the experiments are too expensive, dangerous, or too complicated for students to carry out. In this case, instructors can either film the experiments or provide simulations for students to watch, interact with, and analyze. Some of the reported top challenges for online labs are: lack of support when students have questions; lack of confidence; feeling unprepared; the lack of real, hands-on experiences; and feeling alone without a lab partner. In addition, online labs may not be fully recognized as contact hours for accreditation.
Faculty contact: Dr. Jennifer MacDonald, Jennifer.L.MacDonald@Dal.Ca, Dr. Gianna Aleman-Milan, gianna.aleman@Dal.Ca, Department of Chemistry; Dr. Kalyani Prithiviraj, KPrithiviraj@Dal.Ca, Department of Plant, Food, and Environmental Sciences (Truro)
-
The Hybrid Flexible (HyFlex) model for teaching combines real-time in-person interactions with remote synchronous or asynchronous participation4. To bring this model into the laboratory setting, students could record themselves live as they carry out experiments, while other students could observe online both synchronously and asynchronously. Students could switch roles for different experiments throughout the semester. In addition to the obvious advantage (flexibility), HyFlex labs could help avoid reducing the number of in-person laboratory sessions to accommodate more students. The drawbacks of this method are reduced hands-on experiences for students; increased technical demand (e.g. live recording); and complexity in coordination. HyFlex labs remain a largely uncharted territory at this time. While not an example in teaching labs, Georgia Klein’s FOCUS article on her Hyflex classroom is an instructive case. Read her piece here.
Faculty contact: Dr. Naeimeh Jafari, Naeimeh.Jafari@dal.ca, Medical Sciences
References
1. Enrolment reports and data. (2024). Dalhousie University. https://www.dal.ca/study/registrars-office/enrolment-reports-data.html
2. Communities of Teaching and Learning. (2025). Dalhousie University. https://www.dal.ca/dept/clt/resources/communities_teaching_learning.html
3. The State of Science Labs. (2025, October 14). Science Interactive. https://www.scienceinteractive.com/state-of-the-lab-report/
4. Klein, Georgia. Embracing Hyflex: Enhancing Learning in a Diverse Educational Landscape. (2025). FOCUS. Center of Learning & Teaching. Dalhousie University. https://focus.clt.dal.ca/blog/embracing-the-hyflex-approach-enhancing-learning-in-a-diverse-educational-landscape