In this puzzle, the pieces composing the cross may be made of pasteboard, but are better and stronger if made of the white holly or other thin "bracket wood."
Cut three pieces—with the jig-saw, of course—in shape like Fig. 1, one piece like Fig. 2, and one like Fig. 3.
These pieces may be of any size, but relatively each one must correspond with the sizes and shapes indicated in the diagram.

Cross Puzzle - How to make wooden puzzles for kids - Wooden puzzles plans

Paint as fancy may dictate, after smoothing the edges off with sand-paper. Pack in a box treated.
When the puzzle is given to the little folks, no " key " should accompany it, but the children should try to put it together without help. If, however, you find they begin to lose interest, show them the first step, and encourage them to try to finish it by themselves.
There are great differences in children in this respect; some persevering and unwilling to be helped at all, while others become discouraged at the smallest obstacles and refuse to try. The latter should be encouraged by a little help, care being taken, however, that they do a considerable portion of the work themselves.
No doubt this " indolence," as it is sometimes erroneously called, is generally due to a weak physical condition, rather than to inferior mental powers. A child of this temperament, instead of being ridiculed by his more vigorous companions, should be encouraged and stimulated to action; and such games or puzzles as those contained in this book are just the things to accomplish this end.

Excerpt from the book: How? or, Spare hours made profitable for boys and girls by Holbrook, Kennedy / Publication date 1887 / Publisher New York, Worthington co.