Book excerpt: Happy 30th birthday, Please Mrs Butler! This witty collection of school poems by Allan Ahlberg, re-jacketed for its 30th anniversary and for a whole new generation of school children to fall in love with, is full of typical classroom events that will be recognized and enjoyed by everyone. From never-ending projects, reading tests, quarreling, making-up, excuses and 'Please, Sir, it isn't fair.' Fritz Wegner's line drawings beautifully complement the hilarious and poignant verses. Please Mrs Butler was voted the most important twentieth-century children's poetry book in a Books for Keeps poll.