I read the paperback of the book in my school library and forgot it.
The Plot (if it is correct)
group of children .they has or make a tree house.they use the tree house to peep on a woman and her house(Because of something mysterious)In Her house's compound there is a well.She uses it.the well holds some secret .like it can be dried and a secret romm or some thing..The children make a tunnel.The book is hiliarious. and a war between 2 group of children or the tree house children and someone's elder bro?. one person help's them.And someone frames a prank on the tree house children by damaging their helper's car. And it has other book's too .
Like a ghost typewriter. and other's