Talk to KS2 children about the role of ghosts in literature and how attractive the idea of apparitions seems to be to writers and readers. Can they name other ghost stories? Introduce KS3 children to Dickens's A Christmas Carol.
Choose lines from a favourite contemporary story or poem and illustrate it.
For upper KS2 and KS3 children, Harry Potter and the Order of the Phoenix by JK Rowling is deeply magical and offers excellent topical subject matter for illustration.
KS3 children can experiment with light and dark using silhouettes. First place a light subject on a dark ground, then reverse it and discuss the different visual effects.
Fuseli's witches are in profile. Ask KS4 and 5 students to draw from a model trying different viewpoints. They could start with the complex three-quarter-face view, then try to draw the profile, and then a full face portrait.