A-level Exams Mark Schemes

I have discussed before the problem that Universities have in identifying the brightest students amongst the increased proportion that are achieving A grades. There has been considerable debate about whether the relentless annual improvement in grades is due to a general “dumbing down” of the exams. I have been looking at some of this year’s Biology A2 exam papers and I do not believe that the exams are becoming easier. The exam questions today seem better designed to test knowledge and critical thinking compared to the A-level questions 20-years ago which mainly tested knowledge. So why are students doing so much better than before? I think the problem lies in the highly prescribed mark schemes that the examination boards publish for each paper. These are required to allow examiners to mark each paper with a level of consistency but it also means that the students tend to revise the mark schemes rather than the subject itself. The number of questions that can be asked by the exam boards is somewhat limited and similar questions crop up year after year. The students learn the key points on the mark scheme for these questions and get full marks. Some students even believe that if a key point is not on the mark scheme, then it is not correct even though it might be a correct biological point. There are a few ways in which exam boards could improve the exams to allow a better discrimination of each student. Firstly, new questions need to be set each year that have not been used before so that there is no published mark scheme available. Secondly, the questions should try to get the students to reason/think and come up with sensible answers that might not be included in the syllabus. Examiners should be prepared to accept sensible answers even if they are not on the official mark scheme. AQA questions asking for a “suggested” answer are good at this. Finally, horror of horrors, perhaps the exam boards should stop publishing mark schemes so that the students have to revise the subject rather than the answers just like we had to do in the past.

Exam Marking

Deep in the middle of marking undergraduate exam essays. This can be quite challenging, particularly when the hand-writing is difficult to read. Students are told to write legibly and "those who do not may find themselves at a grave disadvantage". Students will not actually lose marks if an examiner cannot read their writing but they may not gain marks either. Examiners are only human after all, and if they cannot read a particular word, how can you get a mark for it? Examiners have a large number of essays to read through in a short period of time and those that can be easily read are more likely to acquire the marks in they make the appropriate points.  Examples of the wide range of handwriting styles are shown.

University Entrance Grade Offers

Next year’s intake of bright-eyed and bushy tailed students will now know the grades that they have to achieve in their A-levels to get into Cambridge. In general, the average grade offer for Cambridge is A*AA (380 UCAS Points), which is not much higher than a lot of other Universities in the UK. For example, the average grade offer for studying Biological Sciences at Oxford is AAA, Newcastle and Sheffield is AAB and University of East Anglia is ABB. Thus, in terms of grade offers, it is almost as easy to get into Cambridge as a lot of other Universities. BUT, the reality of the situation is more complex than this since the average grade that is actually achieved by Cambridge students is 559 UCAS Points (almost four A*) and as this is the average, some students must be achieving even higher grades than this. So Cambridge students may well be offered A*AA grades to get into the University but in reality they achieve much higher. Cambridge students out perform their offers.  Thus, the most difficult part is to get a conditional offer in the first place. 

 

So how do admission tutors decide these offers? Academics who interview prospective students have a hard time in identifying the best students as A-level grades have shown an inexorable rise over the last two decades (see Figure). In 2000, the proportion of A grades was 17.8% while in 2010 the proportion of A/A* grades was 27%. What this means in reality is that most students who apply to Cambridge will have very high predicted grades. Thus, the interview is particularly important in trying to identify the students to whom to make an entrance offer. Discriminating between students who are all predicted to get three or four A* is very difficult and every year there are well publicised cases of an A* student who does not get a place. Given the number of exceptional applicants, this is not particularly surprising. So admission tutors cannot really use predicted grades in any discriminating way to make offers. They have to resort to different criteria. I know that some Cambridge colleges obtain the AS exam results of the applicants and will only consider candidates that have achieved better than 90%. Moreover, high grades that are obtained after several re-sits will not carry as much weight as those achieved first time around. It is better to be ready and fully prepared for an exam and achieve your best grade at the first sitting rather than do multiple re-takes. In addition, the way in which the student performs during the interview will be very important in securing an offer.

Drug use at Cambridge

An article in the student newspaper “The Varsity” has just published the results of an online survey into the number of students who use illegal drugs while at Cambridge. The headline figure of 63% of students having taken illegal drugs seems very high. Headlines can be misleading however. Firstly, this does not mean that over 60% of all Cambridge students have taken drugs but only those that responded to the survey. The article does not give the number of students who completed the survey so it is impossible to gauge how prevalent drug taking might be in Cambridge. Percentage figures without an indication of the number of students who filled in the survey is misleading. If say 1000 students did the survey, of which 630 had taken drugs to give the 63% headline number, this would only be 3.5% of the total number of students at Cambridge. It cannot be assumed that the rate of drug taking will be the same between those students who completed the survey and those who did not. In surveys of this kind, there will be a bias for drug takers to want to compelete the survey. Why would students who do not take drugs be interested in completing a survey that they would see as irrelevant to them?

The second point is that the headline figure of 63% is a rather blunt instrument to convey accurately the full details of the survey. Reading the article more closely suggests that the breakdown of this headline figure is 61% marijuana, 2% cocaine and less than 1% heroin. Thus, the majority of the students who use illegal drugs are using the Class B drug, marijuana, rather than the more serious Class A drugs.

Snowy Cambridge

The hand of winter finally exerted its icy grip over Cambridge. Heavy snowfall over the week-end carpeted the city in 10 cm of snow and gave plenty of photographic opportunities. Cycling became treacherous but Cambridge is a small city that can be easily viewed on foot. 

Here are some photographs.

Difficult cycling conditions

Not the best weather for punting

Snowy River Cam with trails left by the ducks

Cambridge University Entrance Interviews

Just before Christmas, hundreds of nervous sixth formers arrive in Cambridge for college interviews hoping to be offered a place at the University. The interviews take place in whichever college the student has applied. The form and conduct of these interviews will vary widely depending upon the experience and quirks of the college fellows doing the interview, the subject that the student has applied to study and the academic background of the applicant. The questions that might be asked have often become the stuff of urban legend – for example, would you rather be an apple or a banana?

The questions are aimed at getting the students to think and to identify those who can use their brains. It is very difficult to discriminate between students based on their predicted A-level grades as most are expected to get three or four A-grades so the interview is one of the ways to identify whether the students can think for themselves or have simply been spoon-fed and tutored to achieve high A-level grades. It is unlikely therefore that the students will be asked to regurgitate factual knowledge from their A-level syllabus. Of course, some of the questions will be aimed at putting the student at ease such as why do they want to come to Cambridge, which book are they currently reading, why do they want to study subject X? Most of the students will have prepared responses to these banal questions. The more discriminating questions might require the student to use their A-level knowledge and apply it to situations with which they are not totally familiar. For example, why does a car get more miles per gallon of petrol if the tyres are properly inflated? Why do you often find sand on the bottom of a swimming pool? What might account for the leaves still left on this tree in the autumn?

Some questions will not necessarily have a correct answer such as the apple and banana question, but are aimed at seeing whether the student can give a clear, reasoned argument. For example, what do you consider the greatest scientific discovery of the 20^th century? Antibiotics, structure of DNA, contraception, vaccination? There are lots of possible answers but the interviewer will be looking to see if the student can present an argument justifying their choice.

Of course the process is stressful and certainly not perfect. It possibly favours the more confident students but by asking off the wall questions that are difficult to prepare for in advance, it is hoped that all the applicants are given a fair chance that is not dictated by the quality of the school they went to.