I am currently a student at the University of Warwick coming to the end of my first year of a Mathematics degree.
While doing my degree, I have tutored a number of students in both their GCSE and A Levels for mathematics, chemistry and physics. Some of these lessons were online and some in person but both resulted in steady progress for the students and an overall interactive and informative experience to assist their learning.
Throughout my A level studies, I tutored a GCSE student in an effort to give them a grade 6 (or B) in the end of year exam. This did not only include teaching the skills and methods required for this grade, but also instilling a sense of confidence that they previously lacked. By the end of the year mock exams, they were sitting on a comfortable grade 7 (or A) and were far more relaxed going into the GCSE exams than they would have been several months earlier.
Furthermore, in my second year of A Levels, I mentored a pair of students with Physics for similar reasons as my previous student. They were performing at a relatively high level but lacked both the confidence and commitment that were required of an A level physics student. They are yet to sit their A level exams but over the course of just a few weeks, I was able to see huge improvement with both students.
The progress of these examples was due to us choosing a set topic and working through several different problems surrounding this ranging from shorter 1 or 2 mark questions to longer 6 mark explanation questions (mainly for physics.) We also went through definitions and smaller formulae just to ingrain this knowledge before the exams.