Running the Institution (Part 1): Timetables and Class Allocations Demystified

Reading Time: 7 minutes

By Kate Tan (15S03U), Wilson Chan (15A01C), Tan Yi Chern (15S03N) and Yeo Jia Qi (15S03H)

Press: What can we do to make your life easier? Ms Chen: Submit the matriculation forms by the deadline. My joke is that everyone should take PCME or BCME.

As the Year 5s transition to a timetabled academic curriculum, Raffles Press sheds some light on the behind-the-scenes work that goes into creating the sheet of paper that will define the majority of your weekday hours for the year to come. In this article, Press interviews Ms Chen Yee Chien, Dean of Systems since 2007, to find out more about the down-and-dirty of timetabling and class allocations.


Starting with a light-hearted and humble disclaimer, Ms Chen emphasises that it is actually her timetabling committee that does most of the work, but that she does know “the big picture of how it’s done”.

The long process of conceptualising and organising the sheet of paper that we often take for granted begins with what everyone would expect: lots of data entry. “All the groupings, all the teachers, who is teaching which class or which group” must be keyed in, after which the software is left to run, and the complex back-and-forth dealings with the computer program begin. Lecture groupings are decided by the HODs; in Year 6 they can even request extra tutorial slots based on individual classes’ needs. The timetabling committee will collate the requests and determine if these classes can be given extra slots.

Past years’ experience has given the committee an idea of “the things that will jam up the system” and make the program unable to produce a solution, allowing them to pre-empt such issues and generate a rough timetable (i.e. the first cut) in as little as 15 minutes. This enables several timetables to be generated and compared to each other manually before the best set is selected for manual adjustments to improve it even further.

Naturally, the first step is to schedule all the lessons. While seemingly straightforward, the process is complicated by basic constraints. As Ms Chen explains, “The general rule we work with is, after 4 periods in a row, you should have a break. After PE, there must be a break. There cannot be more than one science practical a day. Lectures must be strategically placed to maximise the possible slots for science practicals as far as possible […] and there should be at least one short day (ending at about 1.30) besides Wednesday. But it’s not possible for some classes.” Subjects that have students drawn from many classes across the level, such as the H1 subjects in Year 6 or English Language and Linguistics, also need to have their tutorial slots carefully arranged to align nicely with each student’s timetable. After this, the manual adjustment process begins: “It’s like playing a game. Every period, every class is called a tile. Then we shift the tiles to empty slots, and the system tells us if we can’t shift. Say we want to shift a math tutorial to an empty tile, but the system tells us we cannot because the math tutor is teaching another class during that period. So we look at it – we might shift out the other class to make room for this class.”

How complicated the timetable really is on the software
How complicated the timetable really is on the software (click to enlarge)

While the constraints of the normal academic timetable are understandable, some question why the days of H3 subjects are so rigidly fixed. As Ms Chen explains, it is a matter of experience. In the past, where H3 timings were more fluid, it became a “nightmare” trying to sort people into classes. Hence, H3 subjects are now fixed on specific days, and it is “you [who are] in charge of figuring out if the H3 clashes with your CCA and whether you can work around it… you have to settle your own issues”.

It’s not just about the lessons though; even breaks are also taken into consideration. Because of the limited capacity of the canteen, the number of classes on break at any one time period must be monitored. Then, of course, comes the issue of venues. Although most of the time there is no shortage of venues, classrooms are almost always occupied – hence the reason why Year 5 classes (with the exception of HP classes) can’t have homerooms. At any one time, some classes must be scheduled in the LTs, or there simply won’t be enough classrooms for everyone.

For students upset at their many seventh-floor tutorials, the crux of the matter is that the software assigns the venues completely randomly: “The software doesn’t know where the venues are physically, so it might assign one period seventh floor, next period second floor, next period seventh floor again.” This means that consecutive tutorials have to be manually adjusted to be held in classrooms that aren’t too far apart. So the last step in the process, concludes Ms Chen, is manually arranging venues to minimise movement between classes, as well as minimise using the A7 and A6 classrooms.

Classroom allocation on the software
Allocation of classrooms on the software (click to enlarge)

The Year 6 timetable is settled first, with slots and venues left for the Y5s. Sometimes the Year 6 timetables will be adjusted slightly when the Year 5s come in, especially concerning teachers that teach both levels. But the Year 6 timetable, lacking Project Work and Mother Tongue, ends earlier and generally is simpler to iron out, especially since Year 6 classes have homerooms, making manual adjustment mostly unnecessary. “Normally, all the classes are assigned homerooms randomly by the computers,” Ms Chen explains, excluding “temporary issues” like wheelchair-bound or injured students, who have priority for the lower floors.

Ms Chen is also involved in setting examination timetables. The challenge, she reveals, is to deal with the “big papers”, namely “GP, Econs, Chem, Math, and Biology and Physics (the last two are always scheduled together). If one level is having these five exams, all the venues are used up!” Generally though, the MPH, ISH and Innovation Centre can hold all the candidates, which cuts down the number of invigilators needed, as compared to using classrooms.

Class Allocation

The process of class allocation concludes before timetabling begins. Classes are sorted by subject combination and so “the biggest problem is really having too many subject combinations within a class”, especially so in RA classes and Arts classes. As Ms Chen puts it succinctly, “The smaller the candidature, the bigger the problem.” Compared to many universities, which set timetables from the start with students choosing themselves which courses to take, the subject combination is selected during matriculation before timetabling begins. This means if classes contain too many combinations, slots cannot be synchronised, and transferring between classes is necessary.

Here, Press takes the opportunity to ask the age-old question  – are classes sorted by ability or GPA? Ms Chen answers frankly, “If there are a few classes left [after sorting by subject combination, H1MT, RA and HP], there is a very loose banding. We don’t go very strictly by GPA only.” She explains that, from experience, having a class of students with similar learning profiles allows teachers to adapt their teaching style and pace to suit the class:

It’s not just by GPA, it’s also by [GPA of] prerequisite subjects, gender mix, racial mix, JAE/RP students mix – and sometimes [the mix of] foreign scholars…

Just like playing a game, the process of allocating classes involves certain rules. On one hand, the Science classes can only have a maximum of 27 students, because that is the maximum capacity of the labs. On the other hand, classes can’t be too small, as there is a set limit of classes per year. If one class has less students, that means another class must have more students, all while staying under the limit of 27 students per class. “It’s a very tight thing, because we try to maximise resources. After all, the more classes we have, the more teachers we need, and the more rooms we need. We don’t have the luxury of having extra teachers waiting to be deployed!” Other considerations also matter, such as Muslim students, who need to be free on Fridays between 12.30 and 2.30 for prayers. So as not to inconvenience other students in the class, “as far as possible, we will usually try to end the day by 12.30p.m. for such classes,” says Ms Chen.

With the criteria for sorting of classes listed out in such a neat order, class allocation might seem like a simple task. However, the very first criteria – that of subject combination – is also the most difficult to accommodate. Reminiscing on past experiences, Ms Chen says, “The old syllabus was very easy. Students took 3 or 4 subjects, and there wasn’t this H1/H2 business. So when the H1/H2 syllabus first came out, the first year was a very painful learning experience.” Now in their 10th year of working with the H1/H2 syllabus, Ms Chen and her committee are far more prepared. “So now we give a disclaimer!” she announces cheerfully, reminiscent of the numerous talks she gives in the MPH. “After Orientation, when we first allocate you into classes, I said this is as far we can as see for now, but I reserve the right to change [your class allocation] 1 week later when the full timetable comes out.” However, she assures students, such cases are few and far between, and will only involve those taking very unique combinations, or subjects with very small candidatures.

But what about those who want to change out of their current class? The Press writers then bring up the ever-familiar subject of Y5 students who wish to change classes and subject combinations after first receiving class allocations. Ms Chen empathises with their situation, but explains her own constraints. “Now (as at the time of the interview), subject combinations are still very fluid. So say I’m sorting the BCMH students, and I have 24. So I find 3 BCM+French students and add them to the class to make 27.” Digressing briefly, she jokes that “third language combinations are my best, like wildcards, can put anywhere! Wherever got vacancy I slot them in!” She continues, “So now, if a BCME student comes and tells me that he or she wants to change to BCMH – too bad! I don’t have space in the class, unless someone moves out. It’s like playing musical chairs.”

When it comes to subject combinations, Ms Chen admits that the committee has not been able to accommodate everyone for the past few years, despite their best efforts:

If you all have a first choice, give me your first choice and don’t change! If you give me at the start, I will definitely give you [the subject combination]. If later then you change, my hands are tied.

Look out for Part 2 of our interview, where we take a step back to consider a broader view about the general logistics of running the school.

76660cookie-checkRunning the Institution (Part 1): Timetables and Class Allocations Demystified


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