There are four new children that term, Julian, a likeable, lazy, clever chap who bothers to make a model plane that flies beautifully but can't be bothered to learn history dates, Martin, a shifty thief and Rosemary, a timid, spineless girl.
When Elizabeth catches Julian stealing biscuits she complains about him, but finds out they were part of the midnight feast menu.
She looks through the big school Book for a case similar to his and reads about a girl called Tessa who behaved almost exactly like Martin.
After knowing the reason why Martin did the things he did, the whole school discussed how they can help him not repeat his wrongdoing again and gave him a chance.
While Julian left Elizabeth to find a special kind of moss, a little child came near the lake she was at and fell in.
To reward her for her courageous action, the Meeting decided to make her an honorary monitor for the rest of that term.
Far more spoiled than Elizabeth was before Whyteleafe "cured" her of her naughtiness, Arabella seems to be obsessed with airs and graces and personal appearance.
His eyes are described as being wide and innocent, but set "a little close together" (one recurring and controversial theme of Blyton is to categorise villains by appearance).
He is kind and generous and appears to help when pupils' property goes missing, by giving them money or sweets apparently of his own.