TORONTO -- A new study suggests up to third of Ontario's kindergarten students may fail to meet provincial standards in reading, writing and math by Grade 3.

The study by the Education Quality and Accountability Office (EQAO) looked at the early progress of over 72,000 English-language students in the province.

It says 29 per cent of students were deemed by their teachers to be "vulnerable" or "at risk" in their language and cognitive development.

Those students were much less likely to meet the standards by the end of Grade 3 than those deemed "ready" or "very ready."

When it comes to reading, only 30 per cent of Grade 3 students rated by their kindergarten teachers as "vulnerable" met the standard for reading in Grade 3.

Forty-nine per cent of those rated "at risk" met the reading standard in Grade 3.

By comparison, 68 per cent of students rated "ready" and 82 per cent rated "very ready" in kindergarten met the provincial reading standard in Grade 3.

The study says the findings illustrate how significant early development is on student learning.

"Overall, Ontario's school system is doing well at bringing most students up to the expected standards for literacy and math after just a few years of schooling," said EQAO executive officer Marguerite Jackson.

"This research shows us that indicators of early childhood development are an important piece of information that both parents and educators should pay attention to as they work together to support the progress of each child."