Exploring Science Pupils' Books Pupils' Books provide full coverage of the Key Stage 3 Science Curriculum and are each divided into twelve units that follow the Units in the QCA Scheme of work. Pupils' Book 9 contains eighteen units -- twelve units that cover the QCA Scheme of Work, plus three additional revision units and three post-SATs project units. Questions in the Pupils' Books get increasingly harder and open-ended and the length of the text between questions is increased to help improve literacy levels. 'Focus on' pages in each unit provide additional extension and enrichment material at the Could know level.