For the past year I have tutored a wide range of ages all the way from key stage 1 to A level. The subject included science maths and the 11+. After tutoring them for months I saw a significant increase in their grades and the approaches they took to answer questions.
Most of the format I use include exam questions and seeing where they are stuck and then on how to improve. This way it gets them ready for the exam questions.
And hour a week for my lessons was enough to go over what they covered that week and build on