Watch videos. that's what I did last year. For science, all I did was watch freesciencelessons made short notes, took me about 3 days to write noets for all sciences then past papers. Subjects like maths are easy, no notes need to be made just dive straight into the questions same with english language & languages. For languages just revise the speaking thing and get it marked by your teacher & you can use it in writing. For reading there are translation so just use memrise to cram as much vocab as possibile which is normally useful for them.