The plot advances in various ways. First, Professor Moody further demonstrates his idiosyncratic teaching style and a willingness to flout MinistryMinstry regulations, as well as an awareness and sensitivity towards students. His decision to teach the three "Unforgivable Curses" has a particularly profound effect on two students: Harry and Neville. Realizing that the Cruciatus Curse demonstration has visibly upset Neville, Moody takes him aside after class and calms him down. Moody also checks on Harry, whose parents he knows were killed with the Avada Kedavra curse that nearly took Harry's life, branding him with a scar, though Harry seems less shaken than Neville. Readers will note that Moody describes the Avada Kedavra curse as killing its victim without leaving any mark. However, Harry's scar was caused by the lethal curse. This is most likely the after effect of the curse rebounding off Harry's forehead, deflected by the protection Harry's mother's death had created.
Also, Neville, who is rarely, if ever, singled out for being good at anything, is extremely flattered and grateful when Moody gives him the Herbology book after being told by Professor Sprout that Neville has an aptitude for this subject. Harry thinks that Moody's gesture is similar to what Professor Lupin would have done.
