CO-EDUCATION, the term applied to the instruction and training of boys and girls, or of young people of both sexes, in the same school or institution, in the same classes and through the same courses of study. Examples of the thoroughgoing application of this principle can be found in every grade of education from the elementary school to the university. But the term “Co-education” is sometimes used in a wider sense, in order to include cases in which boys and girls, or young men and young women of university age, are admitted to membership of the same school or college but receive instruction wholly or in part in separate classes and in different subjects. Other variable factors in co-educational systems are the extent to which men and women are mixed on the teaching staff, and the freedom of intercourse permitted between pupils of the two sexes in class, in games and in other activities of school life. In another form of combined education (preferred by Comte, Système de politique positive, iv. 266), pupils of the two sexes are taught successively by the same teacher. By the English Board of Education, a distinction is drawn between mixed schools and dual schools. “Mixed schools” are those in which, for most subjects of the curriculum, boys and girls are taught together by the same teachers: in “dual schools” there are separate boys’ and girls’ departments under a single principal, but with separate entrances, classrooms and playgrounds for the two sexes.

History.—Co-education in early times was occasional and sporadic. For example, women were admitted by Plato to the inner circle of the Academy on terms of equality with men. The educational endowments of Teos provided that the professors of literature should teach both boys and girls. It is uncertain whether the Roman schools in classical times were attended by both sexes. A tombstone found at Capua represents a schoolmaster with a boy on one side and a girl on the other. Probably co-education was practised in country districts for economical reasons; and also in the home schools organized by wealthier families (Wilkins, Roman Education, pp. 42-43). At Charles the Great’s Palace School at Aachen (A.D. 782 onwards), Alcuin taught together the young princes and their sisters, as well as grown men and women. The Humanists of the Renaissance made the full development of personality a chief aim of education, and held up literary accomplishment as a desirable mark of personal distinction both for men and women. This led to the scholarly education of girls along with boys in the home schools of some great families. Thus, at Mantua (1423 onwards), Vittorino da Feltre taught Cecilia Gonzaga with her brothers and the other boy pupils at his boarding-school; but there is no evidence that the latter was otherwise co-educational. Luther and other Reformers urged that girls as well as boys should be taught to read the Bible. Hence came the tendency to co-education of boys and girls in some elementary schools in Protestant lands. This tendency can be traced both in Scotland and in the northern parts of England. It is believed that, in the early days of New England, district schools in smaller American towns were open to boys and girls alike, but that few girls advanced beyond reading and writing (Martin, Massachusetts Public School System, p. 130). At Dorchester, Mass., it was left to the discretion of the elders and schoolmen whether maids should be taught with the boys or not; but in practice the girls seem to have been educated apart. In 1602 the council of Ayr, Scotland, ordained that the girls who were learning to read and write at the Grammar School should be sent to the master of the Song School, “because it is not seemly that sic lasses should be among the lads” (Grant, History of the Burgh and Parish Schools of Scotland, p. 526 ff.). Meriden, Connecticut, seems to have made common provision for the elementary education of boys and girls in 1678. Northampton, Mass., did the same in 1680. Deerfield, Mass., in 1698 voted that “all families having children either male or female between the ages of six and ten years shall pay by the poll for their schooling”—presumably in the common school.

Thus the beginnings of co-education in its modern organized form may be traced back partly to Scotland and partly to the United States. The co-education of boys and girls, carried through in varying degrees of completeness, was not uncommon in the old Endowed Schools of Scotland, and became more frequent as increasing attention was given to the education of girls. At the Dollar Institution, founded by John McNabb for the benefit of the poor of the parish of Dollar and shire of Clackmannan (date of will, 1800), boys and girls have been educated together in certain classes since the beginning of the school in 1818. In the eastern parts of the United States, where the Puritan tradition also prevailed, co-education struck firm root, and spread chiefly for reasons of convenience and economy (Dexter, History of Education in United States, p. 430). But throughout the west, co-education was strongly preferred in elementary and secondary schools and in universities on the further ground that it was believed to be more in accordance with the democratic principle of equal educational opportunity for the two sexes.

It should be added, however, that the leaven of Pestalozzi’s thought has worked powerfully both in Europe and America in favour of the idea of co-education. His view was that all educational institutions should, as far as possible, be modelled upon the analogy of the family and of the home. At Stanz (1798-1799) he educated together in one household boys and girls ranging in age from five to fifteen. At Burgdorf (1799-1804) his work was in part co-educational. At Yverdun (1804-1825) Pestalozzi established a school for girls close to his school for boys. The girls received instruction from some of the masters of the boys’ school, and girls and boys met at evening worship, in short excursions and at other times.

In England, the Society of Friends have been the pioneers of co-education in boarding schools, both for younger children and for pupils up to fifteen or sixteen years of age. The practice of the society, though not exclusively co-educational, has long been favourable to co-education, either in its complete or restricted form, as being more in harmony with the conditions of family life. Ackworth school was established by the London Yearly Meeting in 1779 for the education of boys and girls; but the school has never been fully co-educational, the boys and girls being taught separately except in a few classes. At Sidcot school, which was founded in 1808 by the Associated Quarterly Meetings in the west of England for the education of children of Friends, boys and girls are taught together, except in certain handicraft subjects. Several other co-educational schools were founded by the Society of Friends during the first half of the 19th century.

Since that time the movement towards co-education in secondary schools and universities has steadily gained strength in England. It has been furthered by the diffusion of Pestalozzian ideas and also by the influence of American example. In England, private schools have made some of the most valuable co-educational experiments. A private boarding and day secondary school on co-educational lines was instituted by Mr W. A. Case in Hampstead in 1865. A co-educational boarding-school was founded in 1869 by Miss Lushington at Kingsley near Alton, Hants. In 1873 Mr W. H. Herford began the Ladybarn school for boys and girls at Withington in the suburbs of Manchester. The passing of the Welsh Intermediate Education Act 1889 led to the establishment of a considerable number of new mixed or dual secondary day-schools in Wales. Many English teachers gained experience in these schools and subsequently influenced English education. The work and writings of Mr J. H. Badley at Bedales, Petersfield, a co-educational boarding-school of the first grade, gave greatly increased weight to the principle of co-education. Important additions have also been made to the fund of co-educational experience by the King Alfred’s school (Hampstead), Keswick school, and West Heath school (Hampstead). In 1907 a Public Co-educational Boarding School was opened at Harpenden.

Since the Education Act 1902 became law, there has been a rapid increase of co-educational secondary day-schools of the lower grade, under county or borough education authorities, in all parts of England. This increase is due to two chief causes, viz. (1) The co-educational tradition of some of the higher grade board schools, many of which have become secondary schools; and (2) the economy effected by establishing one co-educational secondary school, in place of two smaller schools for boys and girls separately.

The idea of co-education in secondary schools has spread in several other European countries, especially in Holland, Norway, Sweden and Denmark. In Scandinavia, the new practice appears to have begun with the establishment of a private higher secondary school, the Palmgremska Samskolan, in Stockholm, in 1876. A similar school, Nya Svenska Läroverket, was founded upon the same model in Helsingfors, Finland, in 1880. In Norway, the law of 1896 introduced co-education in all state schools. In Denmark, as in Norway, co-education was begun in private schools; on its proving a success there, it was introduced into the state schools, with two exceptions; and it is now obligatory in most state schools but optional in private schools (J. S. Thornton, Schools Public and Private in the North of Europe, 1907, p. 97). In Holland, there is now a good deal of co-education in lower secondary schools of the modern type. For example, at Utrecht, the state higher burgher school provides the same course of instruction, except in gymnastics, for boys and girls. At Almeloo, the municipal higher burgher school, though co-educational, differentiates the classes in several subjects. In Belgium, France, Germany and Austria, co-education, though frequent in elementary schools, is regarded as undesirable in secondary; but the movement in its favour in many parts of Germany seems to be gathering strength. All over Europe the Roman Catholic populations prefer the older ideal of separate schools for boys and girls.

Co-education in colleges and universities, which began at Oberlin, Ohio, in 1833, was adopted almost without exception by the state universities throughout the west of America from 1862 onwards. Since that time the idea has spread rapidly throughout Europe, and the presence of women students at universities originally confined to men is one of the most striking educational facts of the age.