Modularising the Lab: independent modules or combined with theory?

The UK HE system has started to re-examine a lot of its structures in light of pressures on finances and ambitions for inclusivity. One of these structures is the module. Modules are a subdivision of the credits within a course - e.g. a 120 credit year may be split into four modules of 30 credits - and typically deal with topic(s) with some thematic coherence in ways which are relatively self-contained. For example, a Chemistry module might deal with models of bonding in ways which stretch across the traditional boundaries of Inorganic/Organic/Physical Chemistry. Or one might deal with Inorganic Chemistry in ways which span the themes of structure and reactivity. There are lots of different ways to modularise Chemistry.

The definition of a module is necessarily fuzzy. Modules vary in all sorts of ways: their size, shape, contents, timetabling, staffing, prerequisites, and internal structure are all very diverse. Nevertheless, modules are now the central unit of delivery in modern UK HE. This is perhaps because management of modules is often more convenient than managing degrees, but may also speak to the undeniable advantages of learner choice: a Physics student can take a Literature module in their first year if Literature modules exist. This is a good thing, as is the scope for a Physics student to pick advanced Physics topics which appeal to them. Recent pushes to economise the module catalogue have been in some tension with the dream of a choose-your-pathway degree, yet it remains common to have some options both within and across degree programmes.

But there are drawbacks to the modular approach. French describes some of these, and I do not propose to make novel arguments. Two of the dimensions which seem particularly troublesome to me are:

  1. Over-assessment of students in a modular regime; and

  2. Reducing the educational focus on holistic engagement with the supra-modular structures of disciplinary knowledge (students ‘leaving knowledge behind’ once the module ends).

I don’t have a strong view on whether the merits of modules outweigh their drawbacks. But I see a strong case for considering how best to administer the module system, given that it is the dominant approach to constructing degrees.

Which brings me to the focus of this blog post: in Chemistry degrees, how should labs relate to modules?

The Chemistry curriculum

Chemistry is traditionally thought of as a practical subject. Jackson’s (superb) Molecular World traces the structures of the early discipline through the specific space of the laboratory. The rich links between the growth of consumerism and the appetite to support training for the chemical sciences were completely central to the genesis of capital-C-Chemistry: it was worth starting up a Chemistry Department because European industries needed Chemists.

This historical trajectory echoes loudly today; the modern Chemistry degree demands that students spend an astonishing number of hours in the lab. Yet in the intervening time, Chemistry has developed sophisticated theoretical tools for understanding and manipulating the atom-scale world. Chemistry is a theoretically-bigger subject than it used to be, and the skills which tempt today’s employers are probably more closely aligned with the theoretical Problem Solving a graduate chemist has developed than their mastery of practical skills.

This tension between practical skills and theoretical insight is one of the central struggles in designing and maintaining the curriculum of a modern Chemistry degree. A graduate chemist has done a lot of lab work, but they also understand a lot of theory in a flexible way which responds to the specifics of the case in question. It’s an extraordinary challenge to fit this into three years.

Institutional perspectives

Chemistry’s volume and diversity of activity is something which contrasts dramatically with other disciplines. Yet a University must develop administrative structures which let it manage modules spanning the whole range: there are organisational benefits to being able to compare a History module built around a seminar series and a Chemistry module with three times the contact hours containing some combination of labs and theory. The centrality of student evaluations owes something to its scope to let managers compare the performances of radically different modules.

Perhaps I am way  off-base, but I have noticed institutional pressures conflict with the disciplinary norms of Chemistry in a few specific patterns:

  1. The volume of coverage demanded by Chemistry is hard to reconcile with institutional guidance on the size of modules (e.g. number of lectures);

  2. The internal subdivisions within Chemistry (Inorganic/Organic/Physical/Analytical) pose particular difficulties for specifying meaningful learning outcomes at the volume permitted by standard module documentation;

  3. Evidencing students meeting these outcomes often demands a high volume of formative and summative assessment, often conflicting with institutional policies on assessment burden.

I acknowledge that there are other problems emerging from these patterns (what happens to timetabling when you have lots of lectures and also block out days for labs?), but I think these three are enough to develop a useful discussion.

The disciplinary differences in the Chemistry curriculum mean that institutional actions often affect Chemistry. If the University pushes to reduce assessment burden or student workload, Chemistry modules will likely be affected at a high rate. I am honestly pretty sympathetic to institutions here: it seems very likely to me that Chemistry over-teaches and over-assesses, and I believe this is doing profound damage to students’ enjoyment of Chemistry. But it is also true that this is what the whole discipline does. If any managers read these blogs, please understand that it isn’t just your chemists who are being difficult - it really is all of us. Sorry!

The modularisation of lab work

Coming back to labs, I want to focus on two common approaches to reconciling lab work with modules:

  1. Labs have their own modules, undiluted by theoretical learning. For example there might be a first year lab module which covers fundamental lab practice and is assessed by academics observing certain skills (weighing by difference etc) and post-lab worksheets.

  2. Lab work is incorporated into modules which also embrace theory. For example, a first year module might include basic synthetic lab chemistry and fundamental organic reaction mechanisms. Assessment might involve lab observation/worksheet and a final theory exam.

Modules with just labs in them have some appealing characteristics. This model allows accountable module leaders to develop a more ambitious sequence of training, and economises some of the work involved in running the lab space safely and sustainably. At the same time, there are some reasons it may not be attractive. The autonomy of a module leader needs to relate meaningfully to the holistic sequence of the degree; the symbolic separation of labs from theory can result in incoherent or inflated demands upon students.

Combining theoretical and practical work in one module also has organisational merits. If you’re doing lab work in your discipline anyway, it can be efficient to use it in the continuous assessment portion of a module’s design. This reduces students’ workload overall (e.g. by replacing a mid-term test on bonding), even if it might be seen to reduce support for learning the theoretical topics. It also has scope to smooth out difficulties in module size: if a University mandates blocks of 15 or 20 or 30 credits (or changes the default module size), a coherent programme of lab teaching can be threaded through several modules to accommodate the sizes of the theory courses. 

At the same time, tethering labs to theory often makes sequencing difficult. In a rota system, for example, labs might be better aligned with theory for the later group (who have touched on a topic more in their lectures). Sequencing at the year-level is hard, too! There is a curious pattern in classical reactions being conceptually simple but experimentally hard and modern reactions being conceptually hard and experimentally simple. Every first year does a bad Grignard reaction, but it would be difficult to situate a nice Suzuki reaction in a first year course if you want students to understand what they’re doing. 

Perhaps this is why it is common to abandon any substantial attempt to align the topics of theory teaching with the content of lab teaching. For example, a lab course might focus on “practical skills” through an essentially-arbitrary sequence of experiments. I see why this is attractive. It allows the lab curriculum to develop coherently in ways which an entangled curriculum does not. At the same time, it draws the focus of lab work away from the theoretical analysis of practical chemical systems. An extreme form of this might even be seen as the ultimate form of modularisation: a lab course so divided from theory that it does not substantially draw on theoretical perspectives. 

We might contrast this with the space practical teaching occupies in other disciplines. Biochemistry typically carries out lab teaching after theoretical teaching about key techniques. Physics typically carries out lab teaching after theoretical teaching about key concepts. Field trip work (Ecology, Geology) is even more heavily supported by classroom teaching, and - perhaps a little whimsically - the “year abroad” model in languages degrees might be seen as a distinctive development in the educational instincts for both preparation and immersion which frame lots of these decisions. It seems descriptively true to me that Chemistry is out of step with other STEM disciplines in how it approaches practical education’s links to theoretical education.

Finally, I think there is an important inclusivity argument around how to negotiate lab-theory modularisation. A student with a “spiky profile” might be superb at lab assessment but get poorer marks in timed exams (or vice versa). If the lab work is all in one module, they might underperform in the other. In extreme cases, this might lead to students failing modules which - if their learning were administered differently - they would have passed otherwise. I think one of the wider points this narrow case illustrates is that how we carry out the modularisation of a degree isn’t a neutral decision, but instead one which embodies our often-unspoken views of what a good performance looks like. In a modular degree, being good at Chemistry is about being good at modules.

Conclusion

I’ve tried to situate the specific decision about module should combine labs and theory in a wider view of what Chemistry is and what institutions are doing. I think my own preference is to combine labs with theory on the basis of student workloads, but I acknowledge that this is really just a response to the culture of a discipline which crams too much into a degree. I see this volume of content as a problem so urgent that it outweighs most other considerations.

But I’d be really interested to hear other perspectives! In particular, I feel that teaching theoretical (particularly analytical) topics principally through lab chemistry is something which hasn’t really been tried. Imagine removing all those NMR lectures and learning NMR in the lab by running a load of experiments. How would that look? More interesting still, I think it would be worth expressing out loud why it might not work. Is it the pace of learning (labs are slow), or the cost of learning (labs are expensive), or the skills being non-practical (labs are not theoretical)? Answering that question in conversation would be a contribution to figuring out how our discipline might best address the modularisation of a subject whose strength is its holistic coherence.