Proposed changes to the exam system in England are likely to cause serious problems for schools, according to the National Association of Headteachers (NAHT).

The union says that in six months time, when the changes are expected to come into effect, there will be an environment of extreme uncertainty for all, with teachers and students unsure what subjects to take and what exams to state, the BBC reported.

As part of the government’s plan to transform education and elevate it to a level where it ends up competing with systems in high-performing countries like Singapore and Hong Kong, it is seeking to make studying more robust and exams more rigorous.

"We face an extended period of volatility,” Russell Hobby, general secretary of the NAHT, said in a press release.

"The cause of this volatility is the sheer scale and speed of changes to the examination system - changes to both the scoring of the exams themselves, and to the way these scores are used to judge the performance of schools."

He did add that not all the changes put forward by the government are bad. It is, the expert went on to say, the speed and scale of the changes that will prove to be problematic.

In this scenario, being able to predict “what will happen and how the changes will interact” is difficult.

“GCSEs are - or should be - two years of focused, determined effort on the part of students and teachers. It is hard to sustain this focus in the face of constant change,” Mr Hobby went on to say.

“The obvious answer is quite simple: slow down and plan the changes better; schedule them far enough ahead to give schools time to react."