The Uniform Mark Scale UMS

The Uniform Mark Scale or UMS is a method of making all A Level scores in the same subject comparable across different exam boards. From year to year and between different exam boards, individual papers may be slightly easier or harder. To compensate for this, students are awarded a mark based on the UMS. Each year the grade boundaries for a paper will typically not be the same. By converting each score to a UMS score, the grade boundaries can be constant on the UMS scale.
At A level, a student may take a number of modules at AS and A2. The UMS scores count equally for each module when calculating the overall grade. Typically a student will want to retake (easier) AS ubits in their A2 year to increase their UMS score and their overall grade, since the easier units count equally toward this grade.
In all subjects (except Maths and Further Maths) the A* is awarded at A2 level for candidates who achieve an A grade overall and 90% or more UMS marks in their A2 units.
For Maths, A* is awarded for an A grade overall and 180/200 or more in C3 and C4.
For Further Maths, an A* is awarded for an A grade overall and 270/300 or more in their three best A2 units.
Unit marks are banked until certification is requested by the School in the Upper Sixth. If a subject is dropped at the end of the Lower Sixth, AS certification will be requested in the Upper Sixth.