In Sydney, it’s known as the ‘Latte Line’, an imaginary boundary that divides the education haves from the have-nots (Ting & Bagshaw, 2016). Largely spanning Sydney’s north-eastern suburbs, the schools above the Latte Line are responsible for producing the bulk of the highest HSC results, when compared with the areas below the Latte Line in the southwest. Although not necessarily as neatly defined, there are similar divisions in the achievements of schools along geographical and socioeconomic lines right across the country. In other words, when it comes to academic success (and I am referring to this in its narrowest interpretation in terms of Year 12 and NAPLAN scores), postcode matters. Much more striking than that, however, is that even within a postcode, socioeconomic advantage makes a noticeable difference to outcomes.

The yardstick for socioeconomic status in the Australian education landscape is the Index of Community Socio-Educational Advantage or ICSEA, a measure that takes into account a range of factors including parents’ occupation and education, geographical location and the proportion of Indigenous students in a school. The ICSEA was created by the Australian Curriculum, Assessment and Reporting Authority [ACARA] “specifically to enable meaningful comparisons of National Assessment Program – Literacy and Numeracy (NAPLAN) test achievement by students in schools across Australia” (ACARA, 2016).

You’re probably already aware that on the My School website, the ICSEA is used to group statistically similar schools so that their results can be compared. Academically selective school James Ruse Agricultural High, for example, with an ICSEA of 1262 topped the English and Maths HSC results in NSW for 2016. Its NAPLAN results (1) are clustered with Hornsby Girls High School (Government selective school, ICSEA 1236), Northern Beaches Secondary College (Government selective school, ICSEA 1232), Perth Modern School (Government selective school, ICSEA 1258) and St Aloysius’ College (Catholic, partially selective school, ICSEA 1240) on My School, and it comes out predictably on top for every Year 9 NAPLAN category. What’s fascinating is that for the three most similar schools in the group, the Sydney government selective schools, the order of the results in every area of Year 9 NAPLAN aligns perfectly with the ICSEA order of the schools (see Table 1).

Although there is no ideal way to compare schools, it is nonetheless an interesting exercise to examine the relative results of neighbouring schools. In Melbourne, postcode 3150 is a case in point. Straddling the suburbs of Glen Waverley, Brandon Park and Wheelers Hill, 3150 is home to no less than four government secondary schools. None of the schools is selective, although strict residential entry zones are enforced, and all are co-educational. Wheelers Hill Secondary College has been allocated the lowest ICSEA of the four, at just over the average score of 1000, while Glen Waverley has the highest at 1097. (See Table 2).

The Year 9 NAPLAN results in Table 2 show a clear divide between the results of the Glen Waverley and Wheelers Hill schools, which are located some five kilometres apart. Brentwood and Highvale Secondary Colleges have very similar ICSEAs and correspondingly similar NAPLAN results, with Brentwood coming out on top in three of the five subject areas and Highvale in the remaining two. Broadly, however, the order of the NAPLAN scores matches that of the ICSEA values.

Real estate
And the cost of real estate also follows suit. Renting a three-bedroom townhouse in the prestigious Glen Waverley Secondary School zone will set you back around $580 a week, compared with $460 for a three-bedroom house in the Brentwood zone and $390 per week for a three-bedroom Wheelers Hill home. (2)

Recent sales support the notion that buyers will pay a premium to be zoned to Glen Waverley Secondary College. In December 2016, vendors received $1.4 million for a two-bedroom weatherboard house in the Glen Waverley zone, while a three-bedroom brick veneer property of similar land size in the Brentwood zone fetched just over $1 million. The median property price in Glen Waverley is $1.2 million, substantially higher than neighbouring Wheelers Hill which is $992,500. (3)

There are, however, two more secondary school options for postcode 3150 that do not require you to live in a particular zone. Wesley College and Caulfield Grammar, elite Melbourne private schools, both have campuses in the district – Wesley in Glen Waverley and Caulfield in Wheelers Hill.

Glen Waverley Secondary College outperformed Wesley (ICSEA 1172) in the 2015 Year 9 NAPLAN tests in three of the five reported areas – Writing, Spelling and Numeracy – the same three categories in which it bested Caulfield Grammar (ICSEA 1141). An entirely accurate comparison is difficult, because both Wesley College’s and Caulfield Grammar’s results reflect the combined outcomes of their multi-campus institutions, and it is therefore not possible to attribute the scores solely to students attending school in postcode 3150.

It’s also important to bear in mind that this analysis represents one cohort sitting NAPLAN in one year. A review of 2013 and 2014 results of these three schools reveals that Glen Waverley had the edge in Numeracy and Spelling while the two private schools did better in the other three subjects, indicating a fairly stable trend in the schools’ results. At more than $26,000 per student a year by Year 12 for Wesley and $28,000 for Caulfield Grammar (‘Compare Schools | The Good Schools Guide’, 2016), it is understandable that parents, particularly those with two or more children, might be willing to pay more to live in a zone for a well-respected school without the high price tag.

Postcode and ICSEA
Postcode 3150 offers a poignant instantiation of the effect of socioeconomic background on school achievement. The 94-point difference in ICSEA between Glen Waverley Secondary College and Wheelers Hill corresponds to around eight to 15 per cent higher NAPLAN scores across the board. Quite obviously, the performance of individual students, and of a school as a whole, is attributable to a huge range of factors, not solely the socioeconomic status of the area. Recent research is, however, showing that the aggregated effect of students’ backgrounds may have a greater influence than has been previously understood.

In a US study, for example, Rothstein (2013, p.61) concluded, “If two groups of children attend equally high-quality schools, the group with greater socioeconomic disadvantage will inevitably have lower average academic achievement than the more fortunate group.” He goes on to observe that, “The negative effects of lower social class status are exacerbated when large numbers of disadvantaged students are concentrated in particular schools” (2013, p.64).

This assertion has especially profound implications for Australia, where our school system actively supports the segregation of students along both academic and socioeconomic lines with the proliferation of independent schools, and in NSW in particular, selective schools. In the 7.9 km² suburb of Carlingford for example, where James Ruse Agricultural High School is located, the other two secondary schools, Cumberland High School and Carlingford High School, have ICSEA values that are only just above the national average, and substantially below that of James Ruse. The NAPLAN results, as can be seen in Table 3, are also significantly lower.

An analysis of Queensland schools by the Australian Bureau of Statistics supports the notion that socioeconomic background is important to school outcomes. “There is a strong relationship between the socio-economic status of the area [SEIFA] in which the child lives, as measured by the SEIFA Index of Relative Socio-economic Advantage and Disadvantage, and NAPLAN performance. Students in the most disadvantaged areas were substantially more likely to score below the national minimum standard for each of the three domains than those in more advantaged areas” (Australian Bureau of Statistics, 2011). Although only geographically one kilometre apart, Cumberland High School sat below the national average in three of the five 2015 Year 9 NAPLAN measures, compared with James Ruse’s strong results in every subject area, a juxtaposition that certainly gives pause for thought.

Given that many of the students from James Ruse Agricultural College probably do not live in the immediate vicinity, it is also worth investigating other Australian research into the impact of the socioeconomic climate of a school regardless of its location. Caldas and Bankston (1997), for example, found that individual academic outcomes need to be considered in the context of both the characteristics of a school’s population and the qualities of the school itself. Most importantly, they suggest that, “The effect of schoolmates’ family social status on achievement is significant and substantial, and only slightly smaller than an individual’s own family background status.”

Much has been made of the achievement gap between Australia’s privileged and most disadvantaged students. While teacher quality and funding have been major areas of scrutiny, Considine and Zappala (2002. p.104) argue that, “the social and the economic components of the socio-economic status equation may have distinct and separate influences on educational outcomes.” The programs and ethos of a school certainly do have a bearing on its ultimate success (Considine & Zappala, 2002; Rothstein, 2013); until we address the broader social issues underpinning school performance, the achievement gap might be reduced, but will never be closed.

Notes
1 All NAPLAN results cited are taken from the My School website and relate to Year 9 in 2015.
2 Prices taken from http://properties.mitula.com.au/ and were correct at time of writing.
3 Sales results taken from: https://www.realestate.com.au/

References
ACARA. (2016). Glossary | My School. Myschool.edu.au. Retrieved 27 December 2016, from http://www.myschool.edu.au/AboutUs/Glossary.
Australian Bureau of Statistics,. (2011). Socioeconomic Factors and Student Achievement in Queensland. Canberra: Australian Bureau of Statistics. Retrieved from http://www.abs.gov.au/AUSSTATS/abs@.nsf/Lookup/4261.3Main+Features32011
Caldas, S. & Bankston, C. (1997). Effect of School Population Socioeconomic Status on Individual Academic Achievement. The Journal Of Educational Research, 90 (5), 269–277. http://dx.doi.org/10.1080/00220671.1997.10544583
Considine, G. and Zappala, G. (2002). Factors influencing the educational performance of students from disadvantaged backgrounds, in Eardley, T. and Bradbury, B. (eds). Competing Visions: Refereed Proceedings of the National Social Policy Conference 2001, SPRC Report 1/02, Social Policy Research Centre, University of New South Wales, Sydney, 91-107.
Compare Schools | The Good Schools Guide. (2016). Goodschools.com.au. Retrieved 28 December 2016, from http://www.goodschools.com.au/compare
Rothstein, R. (2013). Why Children from Lower Socioeconomic Classes, on Average, Have Lower Academic Achievement Than Middle-Class Children. In Carter, P. & Welner, G. Closing the Opportunity Gap: What America Must Do to Give Every Child an Even Chance. Oxford University Press. Retrieved 25 Dec. 2016, from http://www.oxfordscholarship.com.ezproxy2.acu.edu.au/view/10.1093/acprof:oso/9780199982981.001.0001/acprof-9780199982981-chapter-5.
Ting, I. & Bagshaw, E. (2016). HSC results 2016: Sydney divided by education ‘latte line’. The Sydney Morning Herald. Retrieved from http://www.smh.com.au/national/education/hsc-results-2016-sydney-divided-by-education-latte-line-20161220-gtfhpf.html