this "private" "good" school thing is making a fool out of many people, take your child to the nearest public school, especially in Nairobi, the public/council schools are good enough.
unless you are rich or ... enough to hand hold your kid throughout life, then you are much better of in the public school - especially of you would like them to join a public high school, with all the quotas in admission you will be lucky if your kid manages to get into a decent high school from an academy