1980~1990년대 강남 8학군을 둘러싼 사회적 논란과 그 귀결 -서울시 고등학교 학군 문제를 중심으로-

오제연 서울역사편찬원 2024 서울과 역사 Vol.- No.116

이 논문은 1980~1990년대 강남 8학군이 초래한 당대의 사회적 현상과 논란을 통해 강남지역 교육이 갖는 역사적 맥락과 특징을 살펴보았다. 그중에서도 부동산과 교육의 상관관계 및 이에 따른 서울시 고등학교 학군 조정 논란에 초점을 맞추었다. 먼저 강남 8학군은 1980~1990년대 부동산 폭등에 영향을 줬다. 강남지역에 경제적 능력이 있는 가구집단이 늘어나면서 이들은 교육에 더 많은 지출을 하여 교육 수준을 끌어올렸다. 이로 인해 명문대 진학자가 대거 양산되자 강남지역으로의 이주수요 역시 커졌고 이는 결국 주택가격 상승으로 이어져 고소득자의 집중이라는 순환고리를 강화했다. 강남 8학군은 교육 격차 심화의 진원지이기도 했다. 강남 8학군은 교육시설과 교사의 자질 면에서 다른 지역보다 우위에 있었다. 무엇보다 애초 공부 잘하는 학생들이 몰려 있어 입시에서 압도적인 성과를 거뒀다. 이는 고등학교 평준화 정책의 근간을 흔들어 ‘평준화 속의 비평준화’라는 모순을 적나라하게 드러냈다. 1980년대 후반 평준화 제도의 보완 요구가 커지고 강남의 집값이 급격하게 상승하자 정부는 강남 8학군 문제의 해결을 위해 서울시 학군을 조정하고자 했다. 하지만 학생 선택권을 확대하자는 주장과 고교 평준화를 훼손해서는 안 된다는 주장이 맞서며 결국 학군 조정은 이루어지지 못했다. 사실 강남 8학군으로 대표되는 교육 격차와 모순은 단순히 학군을 조정한다고 해서 해결할 수 있는 문제가 아니었다. 그 해결은 교육이 사회 전반의 민주화 및 평등과 보조를 맞출 때만이 가능한 것이었다. This article examined the historical context and characteristics of education in the Gangnam area through the social phenomena and controversy of the time caused by the Gangnam 8th high school district in Seoul in the 1980s and 1990s. Among them, it focused on the correlation between real estate and education, and the controversy over the correction of high school districts in Seoul. First, the Gangnam 8th high school district in Seoul influenced the real estate skyrocketing in the 1980s and 1990s. As the number of households with economic ability increased in the Gangnam area, they spent more on education and raised the level of education. As a result, as many students went to prestigious universities, the demand for migration to the Gangnam area also increased. This eventually led to higher housing prices and attracted more high-income earners to the region. The Gangnam 8th high school district in Seoul was also the epicenter of the widening educational gap. The Gangnam 8th high school district in Seoul was superior to other regions in terms of educational facilities and teacher quality. Above all, there were many students who were good at studying in the first place, so they achieved overwhelming results in the university entrance exam. This shook the foundation of the high school equalization policy, revealing the contradiction of 'non-equalization in equalization'. When housing prices in Gangnam rose sharply in the late 1980s, the government tried to adjust the high school districts in Seoul to solve the problem of the Gangnam 8th high school district in Seoul. However, the argument for expanding student options and the argument that high school equalization should not be undermined confronted, and in the end, school district adjustment was not achieved. In fact, the educational gap and contradiction represented by the Gangnam 8th high school district in Seoul were not a problem that could be solved simply by adjusting the high school districts. The solution was only possible when education was in line with democratization and equality across society.

학군제도에 따른 교육특성이 학군주택 가격에 미치는 시계열 횡단면 영향분석: 중국 천진시를 중심으로

장영,서원석 인문사회과학기술융합학회 2018 예술인문사회융합멀티미디어논문지 Vol.8 No.6

본 연구는 중국 천진시를 대상으로 학군제도 도입에 따른 교육특성의 학군주택 가격에 대한 영향의 시기별 변화를 학군제도가 도입되기 전인 2014년부터 2016년까지 시계열 횡단면 분석하는 것을 목적으로 하고 있다. 실증분석 결과를 살펴보면, 첫째, 학군주택에서 초등학교 및 중·고등학교까지의 거리와 가장 가까운 명문중고등학교까지의 거리가 멀어질수록 가격이 하락하는 경향은 뚜렷해지고 있다. 둘째, 학군등급 및 인접한 중고등학교의 등급 역시 지속적으로 중요성이 강조되고 있다. 셋째, 학군제도가 도입됨으로써 학교와의 거리는 크게 중요하지 않음에도 불구하고 중·고등학교까지 거리의 영향력은 증가하는 현상이 나타났는데, 이는 좋은 학교에 인접함으로써 원하는 학교에 입학할 수 있는 기회를 높이려는 심리적인 행태가 반영된 결과로 보여 진다. 마지막으로 학군제도 도입 전과 후 모든 시기에 걸쳐 교육특성은 천진시 학군주택에 있어 가장 중요한 요인으로 나타났다. 본 연구를 통해 학군제도의 도입은 중국 천진시의 학군주택의 가격변화에 있어 중요한 영향을 미쳤다는 사실을 확인함으로써, 학군제도가 주택가격을 변화시킬 수 있는 중요한 특성이라는 결론을 도출하였다. The purpose of this study is to analyze the temporal effects of school features on school district housing price by introduction of school district system in Tianjin, China from 2014 to 2016. The results of this study show as follows. First, the tendency of price decline is becoming clearer as longer distance from school district housing to elementary school and prestigious secondary (middle and high) schools. Second, school district grades and the grades of adjacent secondary schools are also continuously emphasized. Third, despite the fact that the distance from the secondary schools has become less important due to the introduction of the school district system, the influence of the distance has continued to increase. This can be seen as a reflection of psychological behaviors. Lastly, school features are found to be the most important factors for changing school district housing price in Tianjin city throughout the period before and after the introduction of the school district system. This study concludes that the introduction of the school district system has an important effect on the price change of school district housing in Tianjin, China.

영월지역 초·중등 교육의 변천과 사회적 동인

임경순 ( Lim Kyung-soon ),김동환 ( Kim Dong-hwan ) 세명대학교 지역문화연구소 2007 지역문화연구 Vol.6 No.-

The purpose of this study is to consider the background, special features, and social factors of educational change in Youngwol district after 1945. The results are as follows: First, the leading industries in Youngwol district used to be those of the tungsten mines, Youngwol coal-fired plants, coal mining offices, and cement industries near Sangdong area, but now these industries are on the decline. Second, the education of private kindergartens near Sangdong area was revitalized much more than that of other mining areas around Sangdong town after 1945. It had come in earnest and been generalized by establishing kindergartens annexed to a public school. But most private kindergartens, except those of Youngwol town, have now been closed. Third, over 70 elementary schools used to be established in Youngwol district. Now, there are only 13 elementary schools and 9 branch schools in Youngwol district through the decrease in population and the policy of merging and abolishing small scale schools in farming & fishing communities. Fourth, as Sangdong middle school, which was established as a private school, has turned into a public school, the total number of middle schools in Youngwol district is now 11, which are composed of 10 public middle schools & 1 private one. Except for Youngwol, Jucheon, Bongrae, and Seukjung middle schools, 7 other schools are about 20 students in each school. This is the distinctive feature of middle schools in Youngwol district. Fifth, Youngwol industrial highschool & Jucheon agricultural highschool were representative of highschool education in Youngwol district in the 1970s. But now these schools are suffering, so they are advertising for students. And Seukjung girls' private highschool is so well developed, that it could now be the representative highschool in Youngwol district. Sangdong highschool also shows the special features in Youngwol district very well. It started as a private highschool supported by a local mining industry, but now it has turned into a public school. This was because the mining company supporting Sangdong highschool had great difficulty in running the school. Even though Macha highschool had also been established because of the increase in population through the revitalization of Youngwol mining offices, it has also turned into a very small scale school. Now Youngwol highschool, which is the newest highschool in Youngwol district, is representative of highschools in this area. In conclusion, it is the decrease in population caused by families moving away from the countryside to live in a big city & also the decline of the mining industry, that has had most influence upon the educational changes of elementary & secondary schools in Youngwol district.

서울시 고등학교 학군효과 분석 연구 ―8학군 효과를 중심으로―

성기선 한국교육사회학회 2003 교육사회학연구 Vol.13 No.3

The major concern of this study is finding and explaining the effect of school district on high school students in Seoul city. If we try to find out the effect of school district exactly, we must control the starting achievement level of students and all the other variables which can effect on the achievement growth including socioeconomic status of student, private education experience, individual endeavor, learning style and attitude toward study etc. But because of the data limit, we only control the effect of starting achievement level on the result achievement level. According to the analysis we can know that there are so much difference of achievement level and growth rate between school districts of Seoul. Non the less the effect of District 8 is not more than any other districts especially. We believe that the District 8 is the best area and so many people like to move to this area for their child's education career expecially for top ranking university enterance. For this, the prices of this area's property have been raised so high during last 20 years. This social problem makes other area people be anxious about their child education so abnormally. We can assume that the District 8's educational effect is not higher than common sense. And so the move rush to this area is meaningless if they want to expect this district's high educational effect. I think the superficial effect of this District 8 is overestimated than reality. But it's our duty why the difference of each district's effect size is made. Using more scientifically designed data and multilevel analysis, we must study more deeply this matter. >본 연구에서는 서울시 고등학교 학군효과, 특히 8학군의 효과에 대해서 알아보았다. 학군의 효과는 고등학교 입학 당시 보였던 학생들의 학업성취도 수준이 고등학교 3학년 성취도에 미치는 영향력과 함께 가정배경, 부모의 지원 정도, 개인의 노력 정도 등의 영향력을 통제할 경우 보다 정확하게 분석될 수 있다. 본 연구에서는 자료의 한계로 인해 가정배경, 부모의 지원 정도, 개인의 노력 정도 등 학업성취도 결정에 영향을 미치는 변인들의 효과를 통제하지 못하는 제한점은 있었으나 가장 유의미한 변인의 하나인 1학년 당시의 학업성취도 수준의 영향력을 통계적으로 통제할 수 있었다. 그 결과 일반적으로 8학군이 가질 것으로 믿고 있는 학업성취도에 대한 강한 효과는 뚜렷하게 증명되지 못하고 있다. 이러한 결과는 8학군 자체가 학생들의 학업성취도를 상대적으로 타 학군에 비해 더 많이 끌어올릴 것이라는 믿음과는 배치된다. 반면에 몇몇 학군의 경우에는 상대적으로 성적 향상 정도가 부정적인 사례도 발견할 수 있었다. 다만 서울시 학군간 교육효과 차이가 유의미하게 존재하고 있으며 이 문제에 대한 보다 심도 깊은 연구와 논의가 필요하다고 볼 수 있다.

1976년 경기고등학교 이전과 강남 ‘8학군’의 탄생

오제연(Oh, je-yeon) 역사비평사 2015 역사비평 Vol.- No.113

This study comprehensively deals with the facts and characteristics of the relocation of schools located in Gangbuk, Seoul, which began in the 1970s, and the characteristics and meaning of ‘School District No. 8’ in Gangnam, made based on that. The school relocated from Gangbuk to Gangnam, first in the 1970s was Kyunggi High School relocated in 1976. The reason why the government relocated Kyunggi High School to Gangnam was to disperse overpopulation crowded in downtown in Gangbuk, Seoul to Gangnam. According to the government policy, after the relocation of Kyunggi High School, a number of ‘prestigious high schools’ downtown in Gangbuk moved to Gangnam, one by one. These schools moved to Gangnam according to the policy of the government, but in this process, they made efforts to get the maximum benets from the government, and in fact, they received a lot of preferential treatment. In contrast, the government often showed inconsistent expedient administration. Consequently, based on such preferential treatment and administrative opportunism, with the reform of the school district system in 1980, ‘educational special district’ named ‘School District No. 8’ was created in the Gangnam area. As the prestigious high schools relocated to Gangnam were concentrated on ‘School District No. 8,’ they were combined with the middle class and higher classes around the apartments. In addition, ‘School District No. 8’ in Gangnam produced a large number of successful applicants admitted to prestigious universities through fierce competition for the entrance exam between schools throughout the 1980s. Consequently, with a growing belief that students must go to school in School District No. 8 in order to enter a good university among people, a lot of people were gathering to Gangnam for education. The syndrome of ‘School District No. 8’ which peaked in the late 1980s became calm for the time being as excellent students were gathering to special-purpose high schools since the mid-1990s. However, the Gangnam area is still sending the largest number of students to special-purpose high schools and keeps its privilege as an educational special district, arousing a gust of wind for ‘private education.’

Explaining Local Government Reform

Lee, Jeongho(이정호) 서울행정학회 2019 한국사회와 행정연구 Vol.30 No.3

본 논문은 지방정부인 교육구(school districts)에서 나타나고 있는 정부개혁의 차이를 연구하고 있다. 이를 위해 학교선택운동의 대표적 기제인 자율형공립학교의 운영 실태를 분석하여 정부개혁의 주요 원인이 무엇인지를 밝히고 있다. 콜로라도 교육구(school districts)를 연구분석단위로 하여 수집한 데이터는 다중회귀분석에 의해서 분석되었으며 그 결과는 1) 행정선도자(public entrepreneurs)가 많은 교육구, 2) 정부개혁을 먼저 경험한 이웃한 교육구를 많이 가지고 있는 교육구, 그리고 3) 많은 학생들을 가지고 있는 교육구일수록 정부개혁을 더 적극적으로 추진하는 것으로 나타났다. 한편 본 논문은1990년 대 이후 시장지향적 정부개혁(market-oriented government reform)의 이론적 토대가 되고 있는 학교선택운동(school choice movement) 내용을 한국행정학분야에 소개함으로써 미래 한국정부개혁의 새로운 방향성을 제시해 주는 역할을 한다고 사료된다. In the United States, a school district as a local government has conducted its own government reform by operating charter schools among several school choice movement tools. This article empirically examines why the variation in government reform occurs among school districts. To seek an accurate answer to this research question, this study uses Colorado’s school districts as the units of analysis and tests six hypotheses created by the contents of public entrepreneurs, regional diffusion, and school district attribute factors. The final statistical results demonstrate that three predictor variables-public entrepreneurs, regional diffusion, and student population size-are statistically significant. That is to say, the statistical findings explain that a school district with many public entrepreneurs, many contiguous school districts having previously experienced similar government reform, and many K-12 students is more likely to conduct its own government reform. Meanwhile, this article contributes to developing Korean government reform by introducing the contents of the school choice movement (SCM), which has provided fundamental logic for the market-oriented government reform since the 1990s, to the Korean public administration field.

明代 福建 新縣의 社會ㆍ文化的 變化 ― 縣城을 중심으로 ―

원정식 명청사학회 2011 명청사연구 Vol.0 No.35

During the middle of Ming, the walled district cities of the new districts in Fujian, became nucleuses newly rising in the areas remote from the existing walled district cities. As a regional center, the status of each walled district city varied according to the land size it controled, and the number of towns in it, and its location and land size were marked on maps. On the maps, each district was marked by a symbol of wall like existing districts, and it was listed along with the name of its district school, which made it clear that it was not only a independent unit of tax collection but also a unit of social education producing students and praying for Confucius and saints. In a walled district city, there were city walls, a district office, and a district school, and each of them was its geological, political, and cultural center, so it functioned as a symbol of civilization, a cultural center, an embodiment of national authority, and a shelter in times of troubles. They could be possible because, of all things, its wall marked its boundary and functioned as its defence measures. The seat of a district, when it had not been protected by walls, had lacked the measure for its defence, which had brought social unrests, decrease of population, and consequently no social education had been possible, thus it had been called 'vulgar district'. But once the walls were constructed, owing to construction of social overhead structures such as roads and bridges, establishments of social welfare systems, increase in the number of streets and markets, with growth in population and various people composing it, it became the center of economy and welfare, and all of these show the features of the walled district city. The center in walled district city was the district office and school, and its leader was called district magistrates. As the emperor's representatives, district magistrates had powerful influence on politics and culture in the district, but their governing power was limited because of their regular transfers, and a system which banned the appointment of officials to their native areas, and short financial resources. So they utilized the local influentials such as the upright people or the gentry when doing construction or building works or in relieving the sufferers and the indigent, and they prompted their voluntary participation by granting them tax exemption charters or praising them by setting their name tablets in the district shrine of honor or listing their names in the chapters of biographies in the history of the district, and all of these facts show aspects of the relationships between them. In turn the local influentials had chances to participate in various works, consequently they were granted authority from the government powers. They raised their status in the new district while intensifying their lineal unity so that they could even defy the government authority. Thus, district magistrates tried to maintain stable governing by practicing bad-cop measures, the laws and authority, symbolized by the district offices, aiming to suppress strong-influentials and local-officials, as well as good-cop measures, the spread of confucian culture through education, symbolized by schools. There are lots of books which lay great importance on the district magistrates's personal abilities and emphasizing not only their humane-governing but also courteous-governing, and it shows the situation that district magistrates had faced. The union between the government authority and local influentials brought out the emerging of a group of people called the gentry, and as the influentials in the community, they became the spearheads in the district in carrying out the national policies and spreading the confucian cultures. It was the gentry who diffused the confucian way of funeral, and 3 years attendance on the parent's tombs. Their role could be seen in the fact that the diffusion of confucian culture had been feeble in th... During the middle of Ming, the walled district cities of the new districts in Fujian, became nucleuses newly rising in the areas remote from the existing walled district cities. As a regional center, the status of each walled district city varied according to the land size it controled, and the number of towns in it, and its location and land size were marked on maps. On the maps, each district was marked by a symbol of wall like existing districts, and it was listed along with the name of its district school, which made it clear that it was not only a independent unit of tax collection but also a unit of social education producing students and praying for Confucius and saints. In a walled district city, there were city walls, a district office, and a district school, and each of them was its geological, political, and cultural center, so it functioned as a symbol of civilization, a cultural center, an embodiment of national authority, and a shelter in times of troubles. They could be possible because, of all things, its wall marked its boundary and functioned as its defence measures. The seat of a district, when it had not been protected by walls, had lacked the measure for its defence, which had brought social unrests, decrease of population, and consequently no social education had been possible, thus it had been called 'vulgar district'. But once the walls were constructed, owing to construction of social overhead structures such as roads and bridges, establishments of social welfare systems, increase in the number of streets and markets, with growth in population and various people composing it, it became the center of economy and welfare, and all of these show the features of the walled district city. The center in walled district city was the district office and school, and its leader was called district magistrates. As the emperor's representatives, district magistrates had powerful influence on politics and culture in the district, but their governing power was limited because of their regular transfers, and a system which banned the appointment of officials to their native areas, and short financial resources. So they utilized the local influentials such as the upright people or the gentry when doing construction or building works or in relieving the sufferers and the indigent, and they prompted their voluntary participation by granting them tax exemption charters or praising them by setting their name tablets in the district shrine of honor or listing their names in the chapters of biographies in the history of the district, and all of these facts show aspects of the relationships between them. In turn the local influentials had chances to participate in various works, consequently they were granted authority from the government powers. They raised their status in the new district while intensifying their lineal unity so that they could even defy the government authority. Thus, district magistrates tried to maintain stable governing by practicing bad-cop measures, the laws and authority, symbolized by the district offices, aiming to suppress strong-influentials and local-officials, as well as good-cop measures, the spread of confucian culture through education, symbolized by schools. There are lots of books which lay great importance on the district magistrates's personal abilities and emphasizing not only their humane-governing but also courteous-governing, and it shows the situation that district magistrates had faced. The union between the government authority and local influentials brought out the emerging of a group of people called the gentry, and as the influentials in the community, they became the spearheads in the district in carrying out the national policies and spreading the confucian cultures. It was the gentry who diffused the confucian way of funeral, and 3 years attendance on the parent's tombs. Their role could be seen in the fact that the diffusion of confucian culture had been feeble in the a...

평준화제도의 불평등성 논쟁에 대한 비판적 고찰 - 거주지 중심 학교배정을 중심으로 -

김천기 한국교육사회학회 2005 교육사회학연구 Vol.15 No.1

본 연구는 기본적으로 “거주지 중심 학교 배정”을 하는 평준화제도가 불평등한가에 관심을 가지 고 출발하였다. 단일 학군제를 택하고 있는 대부분의 평준화 지역과는 달리, 복수 학군제를 택하고 있는 서울평준화 지역에서 불평등 논란이 일어나기 때문에 서울평준화 지역을 중심으로 살펴보았 다. 과연 저소득층 학생은 거주지 중심 배정으로 불이익을 받는가? 학력 수준이 높은 8학군 학교에 다닐 수 있다면 학업성취도가 향상되고 상위권 대학 진학률이 높아 질 수 있는가? 본 연구는 이에 대한 논의를 통해 이른 바 “학군 효과”를 새롭게 정의(定義)하고, 이러한 관점에서 저소득층의 학력 상승과 상위권 대학 진학률이 높아질 수 없는 이유를 밝혀보고자 하였다. This study is aimed at exploring whether the policy of assigning students to high schools by their place of residence is problematic in terms of educational inequality in the large urban system of considerable segregation of students among neighborhoods and among schools by class. In this case, the policy of assigning students to high schools by their place of residence is identified as the “Equalization Policy.” Specifically, this study raises the two questions: (1) Is that restricted choice policy disadvantageous especially to the low-income students? (2) If the low-income students trapped in “inferior” school districts are allowed to study in the schools of the affluent 8th School District, is there a possibility that their scholastic achievements will be higher and the ratio of their entrance to the top universities will increase? This study is focused on the High School Districts in Seoul, among which there is stratification by students' achievements and family income. In this study “school district effect,” which was previously used as the meaning of the aggregates of the school effects is redefined as complex effects of interaction among the SES, private education etc. In this perspective, this study has shown why the low-income students could not succeed, even if they should be enrolled the schools in the 8th School District. In conclusion, the low-income students are not disadvantageous especially owing to the neighborhood school policy. This does not support the claim that the policy causes the educational inequality for low-income students. Given that the complex district effect, the low-income students will not succeed in the 8th school district. The policies that could alleviate the problems of complex district effect advantageous to the higher and middle class are required.

초기 청소년의 또래폭력에 영향을 미치는 요인 : 학교환경과 학구를 중심으로

김경집 한국청소년정책연구원 2005 한국청소년연구 Vol.16 No.1

본 연구는 초등학생과 중학생을 대상으로 또래폭력의 가해와 피해행동에 영향을 미치는 개인의 심리적 특성, 가족적 특성, 학생들이 지각하는 사회심리적 학교환경들의 효과를 검증하고자 하였다. 이를 위해 경기도 초등학교 6학년과 중학교 2학년에 재학중인 577명을 대상으로 설문조사를 실시하였다. 결과에 따르면 첫째, 초등학교와 중학교에서 또래폭력을 경험하는 학생이 48.9%로 나타났으며, 가해피해집단의 학생이 41.6%로 나타나 많은 학생들이 학교에서 폭력을 경험하고 학습하고 있음을 보여주었다. 둘째, 개인의 심리사회적 특성과 가족, 학교환경이 학생의 또래폭력과 밀접한 관련이 있었다. 셋째, 학교유형 및 학구에 따라 학교환경에 대한 인식의 차이를 보였다. 넷째, 또래폭력의 가해경험에 영향을 미치는 요인으로는 충동성, 학교유형별 차이가 나타났고, 피해경험에 영향을 주는 요인으로는 피해자의 표적행동 소유 여부와 폭력 허용적 환경이었다. This study tried to explore how an individual's psychological and familial characteristics, and perceived school climates affected bullying among elementary and middle school students. 577 students in the 6th and 8th grade from six different schools in Kyunggi province participated in this survey. Results showed that 1) 48.9% of the students were victims of bullying while 41.6% of the students were either bullies or students being bullied reflecting that schools may be the place wherein one can experience and learn violence. 2) Individual psychological traits, familial structure, and school climate are significant factors that affect bullying especially on the impulsiveness and aggressiveness of an individual. 3) There were significant differences in the perception of school climate by the level of school and district. Students who lived in apartment complexes in big cities were less likely to perceive violence-permissive climates than students who lived in market school districts. 4) Impulsiveness and school level differently affected bullying behaviors and, target characteristics and violence-permissive climate were most important in explaining the victim's behaviors. Based on the results of this study, the significance of this study, the prevention and proper guidance variables related with student's bullying behaviors were proposed.

Within-District School Lotteries, District Selection, and the Average Partial Effects of School Inputs

( Eleanor Jawon Choi ),( Hyungsik Roger Moon ),( Geert Ridder ) 한국경제학회 2019 The Korean Economic Review Vol.35 No.2

This study proposes an econometric framework to consistently estimate the average partial effects (APE) of school inputs on academic achievement when students are randomly assigned to schools within each school district but endogenously sort across school districts. We illustrate our method by estimating the APE of single-sex schooling and class size on standardized test scores using data from Seoul, Korea in the period of 2008-2009. Our APE estimates are smaller than the estimates from conventional linear regressions with school district fixed effects, which do not fully correct for endogenous district choice and thus suffer from selection bias.