My older girl revises by quizzing her little sister. The little one is now winning
The older one has her first set of assessments this month and her method is to sit her younger sister down and quiz her on the science chapter. The water cycle, mostly, and which month is monsoon. Three evenings in, the younger one answers before the question is finished, and the older one has started saying "you weren't supposed to know that one." I think this is no longer revision for anybody but the little one.