Plane Figures: Types of Lines

Age
6-9

Materials

 * A string attached to two small spools.

Presentation

 * 1) The directress, unseen, places one spool in each hand and closes his fists so that the spools cannot be seen.
 * 2) The string passes between the fingers of each hand.
 * 3) Placing the fists together, the children are invited to watch.
 * 4) The directress unrolls the spools as the hands are separated.
 * 5) This is a line, this is a line... As the line grows, the directress changes its position continuously - horizontal, vertical, oblique - still identifying it only as a line.
 * 6) Finally, with the string taut, this is a straight line; and with it drooping, this is a curved line.
 * 7) "A line" cannot exist by itself; it must be straight or curved or a combination of both.
 * 8) Any line that I make will have one of these qualities.
 * 9) The concept of a line goes infinitely in both directions.

Variation
Classified nomenclature and commands.