5.  Perhaps, however, your plan is not the establishment of some new institution, but the introduction of some new study or pursuit into the one with which you are connected.  Before, however, you interrupt the regular arrangements of your school to make such a change, consider carefully what is the real and appropriate object of your institution.  Every thing is not to be done in school.  The principles of division of labor apply with peculiar force to this employment; so that you must not only consider whether the branch which you are now disposed to introduce is important, but whether it is really such an one as it is on the whole best to include among the objects to be pursued in such an institution.  Many teachers seem to imagine that if any thing is in itself important, and especially if it is an important branch of education, the question is settled of its being a proper object of attention in school.  But this is very far from being the case.  The whole work of education can never be intrusted to the teacher.  Much must of course remain in the hands of the parent; it ought so to remain.  The object of a school is not to take children out of the parental hands, substituting the watch and guardianship of a stranger for the natural care of father and mother.  Far from it.  It is only the association of the children for those purposes which can be more successfully accomplished by association.  It is a union for few, specific, and limited objects, for the accomplishment of that part (and it is comparatively a small part of the general objects of education) which can be most successfully effected by public institutions and in assemblies of the young.

6.  If the branch which you are desiring to introduce appears to you to be an important part of education, and if it seems to you that it can be most successfully attended to in schools, then consider whether the introduction of it, and of all the other branches having equal claims, will or will not give to the common schools too great a complexity.  Consider whether it will succeed in the hands of ordinary teachers.  Consider whether it will require so much time and effort as will draw off in any considerable degree, the attention of the teacher from the more essential parts of his duty.  All will admit that it is highly important that every school should be simple in its plan—­as simple as its size and general circumstances will permit, and especially that the public schools in every town and village of our country should never lose sight of what is and must be, after all, their great design—­teaching the whole population to ready write, and calculate.