Cambridge English for Schools
This is without any doubt the worst EFL textbook I have ever used, even compared to things schools I have worked in have produced for themselves. It is quite possible to find whole stretches of 6 pages with no more than 20 minutes of decent classroom material, or whole terms of work on topics your particular students have no interest in whatsoever (e.g. ‘Space’). Shun, shun, shun.