How to use the online timer
Studying fails on starting far more often than it fails on stamina. A defined block with a visible end is easier to begin than an open evening, which is the entire reason timed study caught on: twenty-five minutes is a small enough commitment to make at nine at night, and an open-ended session is not.
These pages cover the blocks that work in practice — a study session, a revision block worked from memory rather than from the page, homework for a school night, a full hour against a past paper, reading, and the plain business of concentrating on one thing without switching. The evening here is often short, since working days start early and school buses come round earlier still, which makes short honest blocks more useful than ambitious ones nobody repeats.
Two things do most of the work regardless of length. Testing yourself beats rereading by a wide margin, however uncomfortable it feels, and spacing the same material across several days beats stacking it into one long evening. Both are harder in the moment and better at the end, which is an awkward trade to accept while sitting at a desk.