Interior and exterior of a circle

Points on the planar surface of the circle within its circumference are said to be interior points and points on the outside of circumference are said to be its exterior points.

Objectives
To understand different planar regions created by a circle.

Estimated Time
30 minutes

Prerequisites/Instructions, prior preparations, if any
The students need to know that the circumference of the circle is its boundary and understand the terms interior and exterior of the circle.

Materials/ Resources needed
Non digital: A meter length wool nailed to ground (to be centre of circle) and tied to stick on the other side to help draw a perfect big circle.

Process (How to do the activity)
Sub units of activity: This is an outdoor group activity
 * 1) Draw a circle on the playground.
 * 2) Make children stand on its circumference.
 * 3) Call one student inside the circle to be a goat and other student on the exterior would be the tiger.
 * 4) The tiger tries to get into the circle interior to catch the goat.
 * 5) All other students on the circumference defend the entry of tiger.
 * 6) If tiger forces itself inside, the goat is let out.
 * 7) If the tiger succeeds in catching the goat, the student enacting goat becomes out.
 * 8) Next two more students come forward to be the next goat and tiger and hence the game continues.

Instructions to the teachers: Let this be a fun filled activity and during the game use the terms circle, circumference, interior and exterior.

Instructions to the students: Identify who is in the interior of circle and who is in the exterior.
 * Evaluation
 * 1) Guage if the students have understood the meaning of the terms interior and exterior.
 * 2) Are the students standing on the circumference of the circle considered to be in the interior or in the exterior ? Justify.