Augmented sixths fall squarely into Romantic theory, and are generally taught after the introduction of the Neopolitan chord (which, contrary to popular belief, is NOT built by having a layer of chocolate ice cream as the root, with vanilla as the third and strawberry as the fifth). It falls under advanced tertian harmony, and will likely be taught in either the third or fourth semester of theory, depending on how quickly your class moves.
Technically, pentatonic scales are neither major nor minor. They're simply pentatonic; as pentatonic scales are not tertian in structure, they cannot be major or minor since those are quantifiers can only be applied to music that is purely tertian. Music that is harmonically quintal in nature can deceptively sound minorish (as can the modal harmonies of eastern Europe and Russia), while harmonically quartal music can sound majorish, but they are not, since modal, quartal, quintal, and pentatonic harmonies are not tertian. When we say pentatonic scale, in general, we usually just mean a scale structured like the black keys on a piano. But in reality, a pentatonic scale can by ANY scale that uses five different pitches in ascending or descending order. So instead of the familiar and standard [F# G# A# C# D#], you could call [F Bb C Db E] a pentatonic scale as well.
Overwhelmed yet? Turn back now while you still can, little one...you know what they say: A music degree is nice to have...that and a buck-ninety-nine will get you a cup of coffee. ^_^