Research shows girls benefit from single-sex environments

In a learning environment that is free from gender discrimination, girls achieve greater academic success and are more confident. As noted by Dr Nicole Archard, in a single-sex school girls are intentionally “equipped with the knowledge and skills required to overcome social and cultural gender biases and in doing so actively break the the stereotypical norms that define women in society” (Archard, 2018).

• UK research has found that girls attending girls’ schools possess higher ‘mental toughness’ scores than girls from co-educational schools, particularly for emotional control and confidence (confidence in their own abilities as well as interpersonal confidence) (AQR International, 2021, pp. 2, 10). Mental toughness determines how a person deals with opportunities, challenges, stress and pressure. It is also significantly linked to higher academic attainment, increased motivation, and enhanced educational outcomes (pp. 5-6, 9).

• Mission Australia’s large-scale annual Youth Survey of young people aged 15-19 revealed that even during the pandemic year of 2020, students at girls’ schools obtained higher scores than the female average in the key areas of physical and mental health, overall life satisfaction, and educational and career aspirations (Mission Australia, 2020).

• A study examining the effect of single-sex maths classes in co-educational schools in Chile has found that they reduce the maths gender gap between girls and boys “by more than half”. This positive effect for girls is achieved without any decrease in the maths achievement of boys. In addition, “this effect is not driven by teacher characteristics or student-teacher gender matching” but by “how female students respond to the gender composition of the classroom” (Paredes, 2021, p. 1)

• An Israeli study comparing the maths achievement of male and female students in single-sex and mixed-sex classes in primary and middle school found that classroom type does not affect boys, but it does have a significant effect on girls’ achievement, particularly for girls in primary school (Skital & Tîru, 2021, p. 31). Where students learn in single-sex classrooms, “the average maths achievement of girls is almost always higher than the average achievement of boys” (p. 34).

• A Jordanian study found that 4th grade girls slightly outperform boys in maths overall, but that girls attending single-sex schools show the biggest advantage in Jordan’s national maths exam outcomes (Al-Bursan, Kirkegaard, Fuerst, Bakhiet, Al Qudah, Hassan & Abduljabbar, 2019, p. 71).

• Fitzsimmons, Yates & Callan (2018, p. 54) found that found that girls educated in single-sex schools are equally as self-confident as boys educated at single-sex schools. This study demonstrates, write the report authors (p. 7), “that at least under one set of conditions, girls in single-sex schools, there is absolutely no gender difference in this important workplace entry attribute”. Also see, Fitzsimmons, Yates & Callan (2021, p. 147) where it is stated that: “In the context of single-sex schools for girls, this study shows for the first time an area where stereotypes and structural conditions are such that men and women can develop equal levels of self-efficacy.”

• A 2018 University of California, Los Angeles (UCLA) study of nearly 6,000 incoming female university students has found that graduates of all-girl schools are more likely to show higher levels of science self-confidence, consider themselves critical thinkers, score higher on measures of academic habits of mind, and demonstrate stronger study habits (Riggers-Piehl, Lim & King, 2018, p. 6).

• Dustmann, Ku and Kwak (2017, p. 28) found that the “the net effect of having single-sex peers for three years is strongly positive for girls”. When classes were converted from 100% female (single-sex) to 50% female (co-ed), girls’ achievement in languages (Korean and English) fell by 8-15% of a standard deviation (pp. 4, 27). (Also see, Dustmann et al., 2017, Why single-sex schools are more successful.)

• A 2017 study of Year 3, 5 and 7 numeracy and literacy (NAPLAN) data by Dr Katherine Dix of the Australian Council for Educational Research (ACER) found that even when socioeconomic status was taken into account, Year 7 girls at single-sex schools were 4.2 terms ahead of co-ed students in reading and 2.8 terms ahead in mathematics (Dix, 2017).

• Data from the Caribbean Secondary Education Certificate (CSEC) for 2013 to 2017 found that girls from single-sex schools in Jamaica, St Lucia, St Vincent and the Grenadines, and Trinidad and Tobago “consistently had a higher pass rate” in mathematics, as well as a higher percentage of distinctions, than girls in co-educational schools, as well as boys in both single-sex and co-educational schools (Spencer-Ernandez & George, 2016, p. 96).

• A 2016 survey by the South Australian Association of State School Organisations found that 61.45% of participants wanted more all-girl public schools offered in South Australia and that 82.88% of supporters of more all-girl school options were educators (p. 1). Participants reported on several advantages of all-girl schooling including academic performance (94%), Science, Technology, Engineering, Maths (STEM) participation (92%), participation in sport (78%), reduced stereotyping (63%), confidence/assertiveness (54%), teaching methods for girls (22%), improved body image (19%), better support (14%), safety (12%) and less bullying (9%) (p. 2).

• In 2014, Professor Alison Booth of the Australian National University wrote in the Sydney Morning Herald that “the evidence is gathering that women in single-gender classes benefit, and they benefit significantly”. In fact, just one hour a week of single-sex education benefits girls (Booth, 2014). Booth et al.’s 2013 study found that female students at Essex University who were randomly assigned to all-female classes in their first year were 7% more likely to pass their introductory economics course than girls in co-ed classes. They also scored 8% higher on their final grade and 10% higher in their required second-year courses, despite only attending single-sex classes in their first year (Booth, Cardona-Sosa & Nolen, 2013, p. 3).

• Even the much-cited 2014 meta-analysis by Pahlke, Hyde and Allison — which concluded that single-sex schools do not provide an academic advantage over co-educational schools — found that there was a “positive effect” of single-sex schooling on girls’ mathematics performance compared with girls in co-educational schools; that there was a small advantage in overall academic achievement for girls in single-sex schools; and that co-educated girls are “moderately more likely” than girls from single-sex schools to “endorse gender stereotypes” (Pahlke, Hyde & Allison, 2014, pp. 18, 20).

• An Australian study has found that girls gain confidence in Information Technology (IT) in single-sex classes. The four-year study, which ran in seven co-ed and three girls-only schools, found that 45% of girls made an unprompted positive comment about their experiences in single-sex IT classes. Feedback from girls included that girls-only classes were more conducive to learning because boys disrupt classes; girls were more willing to ask for help and were more confident and not afraid to try things out without boys being present; and that in co-ed classes, boys put girls down when they were trying to do something or express an idea (Fisher, Lang & Forgasz, 2015).

• In 2015, Andrew Hill of the University of South California found that opposite gender friends have a negative impact on the academic achievement of students at co-ed schools. Students aged 16 and over with higher numbers of opposite gender friends had lower grades across all subjects (p. 148); were less likely to graduate from high school or attend college (p. 173); had more difficulties getting along with their teachers (p. 148); and were more likely to be in a romantic relationship, which “may reduce both the quality and quantity of homework and studying”, as well as being “distracting in the classroom” (p. 171). Hill also found that in students aged under 16, grades in mathematics and science were negatively impacted by the effect of opposite gender friends, and that girls may benefit from single-sex classes in these subjects (p. 168).

• A 2015 study by Eisenkopf et al. identified a “very robust” positive effect on mathematics proficiency for girls randomly assigned to single-sex classes in a Swiss high school (p. 137). The effect was greater for students with high ability in maths and in classes taught by a male teacher, but “the effect also holds for less talented students and for classes taught by a female teacher”. Girls in single-sex classes also “evaluate their mathematics skills more positively and are more likely to attribute their performance in mathematics to their own efforts rather than to exogenous talent or luck” (p. 125).

• A SchoolDash analysis of GCSE results for 2015 found that 75% of girls attending England’s 271 government girls’ secondary schools achieved five good GCSEs compared with 55% of girls attending government co-ed schools, even after adjusting for socioeconomic background and selective intake. SchoolDash founder Timo Hannay wrote that these results are consistent with previous research, including a 2009 study of the Key Stage 2 and GCSE results of 700,000 girls by the Good Schools Guide which found that girls in all-girl comprehensive schools achieved better results than those who attended co-educational secondary schools, and a 2007 government-backed review which recommended that girls and boys should be taught separately to avoid girls being pushed aside in mixed-sex classrooms (Hannay, 2016; also see, Paton & Moore, 2009).

• Park, Behrman and Choi’s 2012 study of South Korean students — who are randomly assigned to single-sex and co-ed high schools — found that “high school female seniors who attend all-girls schools show significantly higher mean scores than their peers who attend coeducational schools” (p. 19). In addition, college attendance data demonstrated that “the four-year college attendance rate for female graduates is 3.1 percentage points higher for all-girls schools than for coeducational schools” (p. 20). The advantage of “all-girls schools over coeducational schools in sending female students to four-year colleges is fairly substantial”, with the study showing that “female students from all-girls schools are less likely to attend two-year junior colleges” (p. 21).

• Dana Diaconu (2012) concluded that girls from Hong Kong and New Zealand “seemed to have benefited more from single-sex education than coeducation” (p. 248). Diaconu examined the Trends in Mathematics and Science Study (TIMSS) databases for 1995, 1999 and 2003, concluding (p. 233) that “for students with similar home backgrounds, levels of self-confidence and academic pressure, girls in New Zealand and Hong Kong were more successful academically and had better attitudes toward science when enrolled in single-sex schools than in coed [sic] schools”.

• Similarly, Suzanne Link’s 2012 study of the 1999 Trends in Mathematics and Science Study (TIMSS) data for South Korean middle schools found “positive effects of single-sex schooling for girls” in mathematics. The effects “are not only highly statistically significant and non-negligible in their magnitude, but also highly relevant since math[s] performance is consistently linked to future earnings” (p. 2).

• An Australian study reporting on a year-long trial of single-sex Year 7 classes at a Queensland primary school found that girls in mixed-sex classes reported significantly reduced scores on emotional and behavioural engagement by the end of Year 7 (Gilmore, Patton, McCrindle & Callum, 2002, p. 1). The study authors write that is possible that the girls in mixed-sex classes were “negatively affected” by the “presence of boys in the classroom” or perhaps they “felt disadvantaged” by not being in the single-sex class for girls (p. 5).

• Belfi et al.’s review of the literature on class composition by gender and ability in secondary school found that “single-sex classes are advantageous for girls’ school well-being and academic self-concept” (Belfi, Goos, De Fraine & Van Damme, 2011, p. 2).

• Veronica Cabezas found that: “Girls in single-sex schools perform better academically than their counterparts in coeducational schools, after holding constant measures of selection, background, peers and school factors” (Cabezas, 2010, p. 227).

• Katherine Bradley investigated single-sex education and its impact on academic achievement, concluding that “the single-sex environment provides females with the best opportunity for academic achievement” (Bradley, 2009, p. 119).