Scales. These are usually not liked by pupils though the benefit to be gained from them is huge. They are a useful way to warm up when practising or performing and help to develop tone and technique.
A colleague once said to me that scales are like a mechanic’s tool box. You can be the greatest mechanic but the vehicle is not going to be fixed with no tools. In music, the scales are your tools. The more you know, the better you will be technically.
The pass mark for scales in exams is 14/21. In grades-one, there are only three scales and arpeggios to learn. This usually consists of two major scales and one minor. It is very easy to earn full marks at this level because there are so few so I usually expect these to be very well known. Grade-two consists of five scales and arpeggios, Grade-three adds a few more and a chromatic. By the time you reach grade-seven and eight, all scales and arpeggios are required numbering over a hundred in total. At the higher levels, it is much harder to earn full marks.
The examiner can ask for them in any order and with any articulation. Staccato=short, tongued=normal, legato-tongued=tongued but broad as possible and legato=slurred (smooth). It is better to play the scales slowly and correct than fast and incorrect. However, the higher grades will require a good knowledge and choosing a tempo that is too slow here will lose marks.