I'm going to be hypercritical about this one for 3 reasons:
1) There is so much (good) poetry to choose from
2) It was written for children
3) It was published by Oxford
I can't be the only person who knew when I was being condescended to as a child. This collection has those poems -- instructional ones about bullying, playing with others, heroic poems about vanquishing French people, etc., but far worse is the whole grim sense of warning. It became especially noticeable browsing it one astonishing day in a grotto of the Blue Lagoon, Gozo.
What a horrible way to make children stop and pay attention. Even the little boys. As Eric Newby says of ad-hoc speeches delivered in front of Ireland's moving statue: "Edifying commentaries on the dire state of everything." Or as a study mentioned in Thinking Fast and Slow showed, people reminded of their own mortality become authoritarian.
Well, kudos for including the amazing "John Barleycorn", by Robert Burns, unheard of by an elderly Scottish woman whose father leads a Burns night every year.
Also, look up "The Gorilla" by Patricia Beer, if you can find it. It's only accidental that both of my examples are somehow related to beer.