Tools and material needed. - A drawing board; some rulers, pencils, erasers, shears and dividers, as were used in the paper series; as many sharp-pointed shoe knives as there are pupils: one-half dozen ten cent cans of Le Page's Liquid Glue; one thousand sheets of white paper, the same as in other series, cut twelve inches by seventeen inches; one thousand sheets of white cardboard, of good quality and a little thicker than a postal card, cut twelve by fourteen inches. Send to some wholesale house for samples, and have the cutting done by them.

The object of this work is to help, in an intense degree, in teaching the many subjects that have to do in a direct way with number and form, and forms the basis of future calculations.

This is taught intuitively and with a great deal of interest, as the pupils think and work out their thoughts. Instead of memorizing rules that others have made through investigation and thought, they make their own rules, compile their own arithmetic and geometry.

The models being made of white card-board, renders them very valuable as a series of models for drawing, and therefore saves the cost of a set made of plaster or wood.

The pupils can invent many modifications of these forms, and no matter how far advanced a class may be in number and form work, these models will always be found useful material.

Such as the following can be given in square and cubic measure: Make a box to contain nine cubic inches. Make a box of different shape to contain the same number of cubic inches.

This is also valuable work for the teaching of concise and correct English, and the pupils become acquainted with the use of terms that are best learned in connection with real work.

The work is done with thicker and tougher material than was used in the paper series, and one sees that, in order to do the work, it requires all the skill of hand and mind formerly acquired, and a systematic growth in both.

To test the real growth of ideas and skill of hand, free hand drawing should be taught in connection with it, and also have them draw the same diagrams of the card-board forms on paper, free hand, then cut and fold.

As the models are arranged in the series one can trace the growth of one form from another, but in some cases forms that should come early in the series are put in later, on account of the difficulties in making; but in such cases they can be made of paper in their true position, and afterwards in card-board.