Poorer children have significantly lower school readiness and vocabulary skills compared to richer children as young as ages 3 and 5, even before starting compulsory schooling. Academics analyzed children and found those from the poorest fifth of the population had average scores that were well below the overall average in areas like school readiness, vocabulary at age 3, and vocabulary at age 5, while children from the richest fifth scored significantly above average. This shows that wealthier children enter school already more prepared to learn and progress compared to their poorer peers.