As someone who does teach economic history, the story is never told simply in terms of AD-AS. That does play part of the story but other points of view are taught -- the various monetary theories (Friedman and Hayek have very different explanations); the various Keynesian views; but also the various structuralist views and Schumpeter's ideas on cycles. Giving only one view would give student's a incorrect picture of the economics profession. As this list demonstrates endlessly, economists rarely agree. Rod Hay