I don't think there will be a need to teach irreligion or atheism in schools. Teaching scientific knowledge and the scientific method, as well as critical thinking and philosophy will suffice and the number of non religious students will rise - That is already happening, millenials and generation Y are the generations with more access to education, public or private, and are also the most irreligious ones
Whoever fights monsters should see to it that in the process he does not become a monster. And if you gaze long enough into an abyss, the abyss will gaze back into you
