In plain words
If we follow wherever it goes, we too turn into monkeys along with it. So once that monkey and this monkey get together, they will not keep still. They will start picking quarrels. That is their nature.
So, if we are to keep the mind on the right path, we must keep at our practice at this very age. Our practice is this: playing some games, singing some songs, and cutting down our talk. Control of this kind we must achieve by deliberate effort. If you need something more, read books, study the great texts. Students! You should not talk too much. What happens through too much talk is that little by little it hardens into a habit and turns into quarrelling. Children must try to live happily always. Even if some worries come, push them aside at once. If anyone says something harsh to you, you must try to forget it without taking it to heart.
Evenness is the mark of Viveka
Only when you practise like this from this age can you hold up ever so sacred an ideal in the days ahead. Alongside your studies we must make a habit of some disciplines of this kind as well. We must grow in the divine qualities of patience and fellow-feeling. Evenness is a mark of Viveka. More than that, brahmacarya is the touchstone of true morality. Humility is the true touchstone of learning. Our selflessness is the touchstone of the highest state. Students must try to achieve these four in the right way. Evenness, humility, selflessness, brahmacarya: if any one of these is lost, you lose your humanness.