Based on the book "Matilda" by Roald Dahl, Miss Honey became alert when she noticed Matilda's extraordinary intelligence and abilities.

• Initial Observation: Miss Honey first became aware of Matilda's unusual intelligence when Matilda was only five years old and in her class. She observed Matilda's advanced reading skills and comprehension, far beyond what was typical for children her age.
• Growing Suspicion: As Miss Honey continued to teach Matilda, she noticed more signs of her exceptional abilities, including her mathematical skills and general knowledge. This led Miss Honey to suspect that Matilda was a child prodigy.
• Confirmation and Concern: Miss Honey's suspicions were confirmed when she tested Matilda further and realized the full extent of her genius. She also became concerned about Matilda's home life, as her parents neglected and mistreated her.

Miss Honey's alertness was triggered by the clear evidence of Matilda's remarkable intellect and the desire to help her reach her full potential, despite the challenges she faced at home and school.