There were rigid gender issues. It was not masculine to spend time with girls. Tom Brown's mom doesn't "get in the way."
Children were sent to either Public school or Private school. Public schools allowed games, the chance to gain autonomy, and to find camaraderie in gaining a moral education. It taught them about nationalism and citizenship.
Thomas Hughes writes about the importance of standing up to bullies like Flashman as seen on p. 211.
It'is known that Hughes wrote this book when his own son was about to go off to school, and it was advice for him. Thomas Hughes went on to found the Christian Socialist Movement which was considered to be "muscular Christianity." The core ideas were to protect the weak, including being against slavery. He even came to the U.S. and founded a utopia in Rugby, TN. On pages 316-317, Thomas Hughes outlines his beliefs that one must devote their life to good works and to not fear death.
This book also teaches that it's important to have faith in the system and to follow the adults in charge. It is also important to follow your conscience, as on pg. 302. Here it states that if you're defending something good, then stand up.