You may be interested in this review of Robin Lane Fox's magnum opus, The Classical World.
Tom Holland, the reviewer, is impressed by the erudition, but finds the book dismissive of the latest scholarship and at times showing some boredom. But read the review for yourself. There have been many reviews of this book, which Google will find for you, and which could be useful if you are considering buying the book for the school library.
Also in the Guardian is this review by John Man of The Fall of the Roman Empire by Peter Heather. He called the book 'magisterial.' Sounds good, but yes, I know, it's not on the A level syllabus.