An Auckland woman who caused the death of a teen cyclist later dressed in a prisoner's costume for Halloween and wrote "hide your children" online.

Rouxle Le Roux had been drinking and smoking marijuana on the night she got behind the wheel of a car and crashed into 15-year-old Nathan Kraatskow.

Nathan Kraatskow died after he was hit by learner driver Rouxle Le Roux in Auckland in May.

Le Roux was on her learner's licence. She and her friends didn't stop. They left the teen at the scene on Auckland's North Shore's Oteha Valley Rd, where he later died of his injuries.

Le Roux avoided a jail sentence when she appeared at the Auckland District Court on Friday, having earlier pleaded guilty to dangerous driving causing death.