Astute observers will have noticed that the IB Chemistry Diploma exams were labelled TZ0 this year. From the very first IB Diploma exams back in the early 1970's until 2007 there was always just one set of May exam papers. This was taken by all diploma (and certificate) students wherever they were in the world. However in May 2008, in response to concerns that there was up to 24 hours difference between the times when the exam was actually sat in different parts of the world, the IB introduced two different exams TZ1 and TZ2 (with TZ standing for Time Zone). Since then there have always been two different sets of examination papers in May, although still only one in November. That is until this year when the IB reverted back to just one common exam. This happened not only in Chemistry but also in Biology and Physics as well.

When they introduced the two different exams back in 2008 the IB said at the time that in some years there might still be just one common set of examination papers. This was so students (and teachers?) could not know whether the exam for the other time zone was different or not and was an attempt to stop them passing on electronically some or all of the content or answers. It is also for this reason that no one is allowed access to the papers or allowed to comment upon them publicly until 24 hours have elapsed.

In fact two exams, TZ1 and TZ2, were written for this session. This means that the IB has one whole set of exams held in reserve. This is probably a sensible position to be in so that they have available a fresh set of papers if any of the intended exam papers do become compromised in some way.

I can see why they chose this year to have the same paper for all the sciences. It is a new programme and at the standardization and grade award meetings it will be much easier to ensure parity over the whole cohort. In the past there has been some concern that the students in one time zone tended to perform better that the students in the other time zone.  Even using the grade descriptors and the experience of many senior examiners it is extremely difficult to ensure that two different sets of answers to different examination questions are graded exactly equally.

The downside for teachers is that until November there will only be one set of genuine examination papers on the new programme to use as practice for students. However this is possibly a small price to pay for uniform standardization. Next year they will have to have two papers (or at least change the designation from TZ0) as otherwise the possibility of dishonesty by electronic means cannot be discounted.