Comenius conceived and published a practical way of teaching languages, one edition of which in 1658 was the first children's picture book. He also published three history books about the [[Bohemia]]ns.<ref name=eb/>
With ''The Great Didactic'', completed in 1631<ref name=nie/>, Comenius presented his theory of education, which promoted a democratic form of education<ref name=etw>Meiklejohn, Alexander (1942). ''Education between Two Worlds'' (New York: Harper and Bros.), book 1, ch. 2, pp. 20-21.</ref> centered in the liberal arts,<ref name=pp>Adler, Mortimer J. (1984). ''The Paideia Program'' (New York: Macmillan), p. v.</ref> but including the instilling of piety and morals.<ref name=gd>Comenius, Johann Amos (1633). ''The Great Didactic'', translated by M. W. Keating (London: Adam and Charles Black, 1907).</ref> He purported to use the scientific method in his conception of education. The ''Encyclopedia Americana'' believed he succeeded in co-ordinating a sound theory of educational ideals in spite of a lack of scientific rigor,<ref name=ea>"Comenius, Johann Amos" (1920). ''Encyclopedia Americana''.</ref> but the ''New International Encyclopedia'' believed he faithfully followed in the footsteps of [[Francis Bacon]]'s application of a new scientific method to the subject of educational theory.<ref name=nie/> Comenius was also one of the first to advocate the teaching of science in school.<ref name=eb/>
In his lifetime, Comenius enjoyed an exalted reputation in educational theory, but was denied the opportunity of executing it on a large scale on behalf of important audiences interested in seeing it applied in their spheres of influence. He was invited by British Parliament to use his theories to reform the schooling of Great Britain, but the use of his methods lost out through Parliament using [[John Locke]]'s prescribed methods instead.<ref name=etw>Meiklejohn, pp. 13-14.</ref>
He was then invited to reform Sweden's schools, but when the Poles invaded the city where he lived, he lost nearly all his manuscripts during a fire.<ref name=eb/> After Comenius moved back to Lissa beginning in 1654, he again lost many manuscripts during a war in Poland.<ref name=ea/>