There is lot of information on this forum. You just have to look at the index.
Following is pasted from an earlier post.
See the post from Patricia - the forum's guru on VRviewtopic.php?f=12&t=4782
Also see the post from saimaj21viewtopic.php?f=30&t=24915
Choose tutor carefully, if you want to engage one - as most of the tutors (including some big names) are little more than glorified class assistants. All they have is a large collection of practice papers which they photocopy (copy rights ??) and hand out to the children. At the end, they read out the answers and the papers are corrected/marked by children themselves. Little teaching of techniques etc. Only the children who are bright and have worked on the 'how to do' books & learned techniques at home can have some benefit from such tutorials (aka practice sessions). A tutor who spents atleast 15-20 minutes per session teaching good techniques and then let children do some practice is an invaluable help in the quest for the place in grammar school or even indies.