In the Memorandum from the Girls’ Schools’ Committee of the Mathematical Association, published on pages 13-15 of the Mathematical Gazette for January, 1926, we are told that the Committee deprecates the use of the term “inferiority” as applied to girls’ mathematical work by the Report on the Differentiation of Curricula between the Sexes. Further, the Girls’ School Committee says: “Where boys and girls are given equal opportunities, as in some mixed schools, the consensus of opinion is that very little difference in capacity between boys and girls is shown in work up to Matriculation standard….” It seems desirable that the question should be put on a sound basis, and with this in mind the writer has endeavoured to draw on material available to him for a statistical inquiry into the points involved. For the last two years he has been engaged in teaching in a mixed school where the boys and girls are taught mathematics together by the same teacher in the lowest two forms, and the forms are chosen on a basis of general standard in school work. The marks are given below. In each case the marks are those obtained by equating the quartiles (by a modification of a method due to Prof. Nunn and given by the writer in the Forum of Education in papers in 1924 and 1925) to 40 and 60, in homework, weekly tests, and terminal exams. The two marks given are those obtained at the ends of the Christmas and Midsummer terms.