Whether to separate twins in school:scientists are exploring the issue

4 May 2018

An international team of scientists from Tomsk State University, Goldsmiths University of London, The GRIP (Group for Research in Intensive care in Pavia), and several other universities in the UK, Australia, and China has published an article, “Twin Classroom Dilemma: to Study Together or Separately?” in Developmental Psychology. The lead author of the study was Yulia Kovas, Professor of Genetics and Psychology, Director of the International Laboratory for Interdisciplinary Investigations into Individual Differences in Learning (InLab), Goldsmiths, University of London, and the head of the International Centre for Research in Human Development (ICRHD) at TSU.

The study, which analyzed data from more than 9,000 twin pairs in schools in the UK and Canada, showed that, on average, their separate or joint education does not have a significant positive or negative impact on academic achievement, cognitive ability, and motivation. This suggests that there should not be strict rules for teaching twins in the same or different classes.

Earlier studies devoted to the contribution of the separate classroom placement of twins to their academic performance had some limitations and gave contradictory results. Despite this, a survey conducted among parents of twins from the UK in 2015 showed that every fifth British school implemented a policy of separate classroom placement of twins.

According to the results of the survey of 514 parents of twins from the UK, 60% of parents of monozygotic and 55% of parents of dizygotic twins would like their children to study together. However, in about 20% of cases, schools pursue a strict policy of separate education without prior consultation and consideration of the views of the children.

- We do not say that separate learning has no effect, rather, the results of the study suggest that there is no evidence in favor of strict rules for joint or separate education because of being better for their academic achievement or motivation. The decision on how to teach the twins should be taken together by parents, teachers, and twins, based on their individual needs, - says Professor Julia Kovas.


Yulia Kovas and colleagues analyzed data from 8,705 twin pairs aged 7 to 16 from the British twin registry TEDS (Twins Early Development Study)  and data from 426 twin pairs aged 7 to 12 from the Quebec study of newborn twins (Quebec Newborn Twin Study).

The TEDS data includes 3,039 monozygotic and 5,666 dizygotic twin pairs, and the Quebec Newborn Twin Study includes 182 monozygotic and 244 dizygotic twin pairs.

Academic achievements were measured on the basis of performance reports. For example, for twins in the UK, these included the results of the GCSE (General Certificate in Secondary Education). Cognitive abilities were assessed using verbal and non-verbal tools. To determine academic motivation, children evaluated themselves, answering questions such as, “I like math” and “Reading is easy for me”.

The study found almost no effect of separate learning, regardless of age, country of residence, gender, or zygosity (whether the twins were monozygotic, “identical” or dizygotic, non-identical). Twin pairs at age 12 (Quebec, Canada) and at age 16 (United Kingdom) were slightly more similar on achievement if placed in the same classroom, with slightly greater similarity among monozygotic twins.

Scientists believe that further research should be carried out taking into account the different models of educational systems in different countries, as well as the impact of separate or joint learning on emotional and behavioral characteristics.