It is often assumed that differences in teacher characteristics are the main source of variability in children’s educational achievements. Estimating and understanding teacher effects is important not only for gaining insight into individual student performance but for guiding investments in teacher training, career advancement and remuneration.

But ongoing twin research by Professor Brian Byrne and Dr Will Coventry at the University of New England in NSW is challenging some of these long held assumptions.

The researchers first began looking at student reading ability in 1999 with the help of identical and non-identical twin pairs from Twins Research Australia. They have since extended their research to include NAPLAN results (National Assessment Program: Literacy and Numeracy), with the cooperation of over 2500 families of multiples registered with TRA.

"To follow the public debate on why some children prosper in school and others falter, you’d think it was all down to teachers," says Professor Byrne. "The media as well as public figures and politicians are quick to blame any student failures on inadequate teaching."

However, his research has found there is a complex interplay of genetics and environmental factors happening in the classroom. Some findings so far include:

• Many factors affect a child's progress including heritable or genetic factors, classroom environment, classroom peers, as well as individual teachers.
• Previous education researchers held that teacher quality will show up most clearly when a child has a "bad" teacher several years in a row. In the UNE research, there was no support for that idea.
• Teachers are doing a much more equal job in fostering early literacy and they have less to do with differences between students’ reading achievement than often supposed.
• Interestingly for parents of twins, the researchers found twin pairs who were in separate classes from each other were almost as similar to each other in literacy development as twins in the same class.