Tree far to tall and over grown

We have been told that the trees that are growing at the end of our garden in the grounds of St Nicolas School are looked after by Oxford country council. The shool have told us that there is nothing they can do, because it up to the above council to tell them what to do with them. We are residents of Fairfield place and we all back onto the school and we all have trees at the end of our gardens. We wish to have the hight of the trees reduced. They are nearly double the hight of our houses BUT DUE TO THE HIGHT AND THE THICKNESS OF THE TRESS THEY ARE BLOCKING MOST OF THE SUN LIGHT FROM OUR GARDENS. We would like the tree hight reduced to the hight of our homes and also all the over hang into our gardens removed.