You have to have some sympathy for the Island’s senior school administrators and teachers. With one group of students and staff forced to move out of CedarBridge Academy during the mould crisis, a pay dispute with teachers and the battering the education system took in the Hopkins Report, both CedarBridge and Berkeley turned around and produced remarkable improvements in their graduation rates.

And while they have been rightly praised for the improvement, the turnaround has also been met with a certain amount of scepticism.

That’s because the improvement was almost too good, rising from a rate of 48 percent to 82 percent in just 12 months.

As Shadow Education Minister Grant Gibbons noted, that begs the question of just what happened in the two schools to produce such a change and why don’t we know about it? And how did the Hopkins Report team, who admittedly did not spend that much time actually visiting individual schools, miss it?

So far, the Ministry of Education isn’t saying, apart from the suggestion that the students were just brighter this year.

Certainly, school principals and teachers will tell you that they all experience some years where students seem to be more engaged and switched on. By the same token, you can have other years who are switched off. But even then, a 34 percent increase is remarkable.

One clue lies in the number of students who were in the graduating class. In 2006, 148 students gained a Bermuda School Certificate out of 309 S4 students. This year, there were 173 graduates out of 212 S4 students.

So the number of students graduating rose by 25 students or 16.8 percent. But because there were almost 100 fewer students in the S4 year, the actual graduation rate soared.

Was this because fewer students entered high school four years ago than in the previous year, or were there dropouts and transfers along the way? So far, no one is saying.

It has been suggested that the reduction in the class size has occurred because the Ministry now actively discourages “social promotion”, the process by which failing students move up to the next year in order to stay with their age groups. If that policy is in place (and it certainly is at Berkeley), this newspaper supports the Ministry, but the public needs to know if it is contributing to the improved graduation rate.

That also adds weight to the idea that the best measure of graduation is to start with all of the students who entered senior school and then to track how many actually made it to the finish line. That would give a truer record of the performance of the senior schools as opposed to a snapshot taken from the final year.

To be sure, some allowance would have to be made for students who may have transferred during their school careers, either to local or overseas private schools, to home schools or into alternative education. But at least then, the Ministry would have some idea of the true success rate.

Finally, there has been some suggestion that grades have been inflated to improve the figures. This seems unlikely, but would not be unheard of. There has been a lengthy debate in the UK about this very subject and universities and employers have complained that the increase in A grades at A Level make it virtually impossible to determine who is a top student and who is not.

However, it would be interesting to see if GCSE results in the senior schools, at least among those who take them, have seen the same improvement rate as the graduation rate. If they have, that would go a long way to dispelling any fears that the graduation improvement is inaccurate. None of this should be taken as a criticism of the students or teachers at the senior schools students. It has to be assumed that the successful students earned their diplomas. But it is essential that the graduation system is seen to be credible.