rse,--comes first; astronomy next; chemistry, geology, and certain
forms of physical geography (weather, volcanoes, earthquakes, etc.)
come third; biology, with physiology and hygiene, is a close fourth;
and nature study, in the ordinary school sense of the term, comes in
hardly at all.

The chapter headings of this book might indicate that the course
has to do with physics and chemistry only. This is because general
physical and chemical principles form a unifying and inclusive matrix
for the mass of applications. But the examples and descriptions
throughout the book include physical geography and the life sciences.
Descriptive astronomy and geology have, however, been omitted. These
two subjects can be best grasped in a reading course and field trips,
and they have been incorporated in separate books.

The best method of presenting the principles to the children was the
next problem. The study of the questions asked had shown that the
children's interests were centered in the explanation of a wide
variety of familiar facts in the world about them. It seemed evident,
therefore, that a presentation of the principles that would answer
the questions asked would be most interesting to the child. Experience
with many different classes had shown that it is not necessary to
subordinate these explanations of what children really wish to know to
other methods of instruction of doubtful interest value.

Obviously the quantitative methods of the high school and college were
unsuitable for pupils of this age. We want children to be attracted to
science, not repelled by it. The assumption that scientific method
can be taught to children by making them perform uninteresting,
quantitative experiments in an effort to get a result that will tally
with that given in the textbook is so palpably unfounded that it
is scarcely necessary to prove its failure by pointing to the very
unscientific product of most of our high school science laboratories.

After a good deal of experimenting with children in a number of
science classes, the method followed in this book was developed.
Briefly, it is as follows:

At the head of each section are several of the questions which, in
part, prompted the writing of the section. The purpose of these is to
let the children know definitely what their goal is when they begin a
section. The fact that the questions had their origin in the minds
of children gives reasonable assurance that they will to some e