In Fear, Itself, Giles says, “It’s alive!”, which is from the 1931 movie Frankenstein. Buffy’s “Fire bad” line in Beer Bad also comes from that movie. The monster in the movie (played by Boris Karloff) is chased by angry villagers with torches, when he shouts, “Fire Bad!”
In Goodbye, Iowa, the shot with Adam and the little boy is an homage to the 1931 movie Frankenstein. When Frankenstein’s monster escapes, he walks through a forest and comes upon a little girl, Maria, who is throwing flowers into a pond. The monster joins her in the activity but soon runs out of flowers. At a loss for something to throw into the water, he looks at Maria and moves toward her. In all American prints of the movie, the scene ends here. But as originally filmed, the action continues to show the monster grabbing Maria, hurling her into the lake, then departing in confusion when Maria fails to float as the flowers did. This bit was deleted because Karloff - objecting to the director’s interpretation of the scene - felt that the monster should have gently put Maria into the lake. This scene is restored in the video cassette reissue. Both monsters were created using body parts from other people/demons and both encountered a child and expressed curiosity, which ended in the child’s death.