Suganthi - if you are ask me then I would say starting preparation at year 4 is waste of money and efforts - I know some people may not agree with this.
if you really wanted to do something then you can pick up Vocabulary Books (FPTP) , some mental Maths books (Schofield & Sims Ltd) and do it at home to give routine practise or Bond books for Year 9-10 series and do it at home.
you can start main preparation at year 5
& pleasantly surprise that Big Bro - QE not in loop.

if you still need some coaching class info, I can send out tomorrow by PM - they are based in Ilford I believe - I need to get details from someone.