Tunmore (cited in Regel & Roberts, 2002, 73) outlined various mental health promoting factors (based on evidence) that are relevant to adolescent kids and to parents alike to reflect upon. They include:
Individual
Family (Group)
Environment
Whilst there are some important factors here, you need to have a bit of caution in places, because for example a high morale school is clearly a value-laden assumption. It is not unreasonable to argue that for some well off children, they are at greater advantage economically and socially, than their poorer counterparts, in gaining a quality education. However if this could be achieved then yes a high morale school as described could be beneficial for social and emotion health.