Loads of children do it at my son's school (he is in Y1). They go to Saturday classes and possibly the summer school too, I'm not sure. Some people wear by it and credit it with a significant improvement in their child's reading. I don't have direct experience as my son hasn't been but his reading has also significantly improved over the same period (it just seemed to 'click') for him and we've just done regular reading with him of the books he brings home from school and read more difficult / interesting books to him at bedtime. Just the normal stuff.