1. The first activity can be where you choose three students holding papers titled INPUT, FUNCTION and OUTPUT. The students with INPUT and FUNCTION can choose their own values while the student with OUTPUT will have to give the answer. Students can be rotated. After that teacher can relate INPUT to DOMAIN and OUTPUT to RANGE. The reverse of the above activity will help explain the concept of INVERSE FUNCTION.
2. The above activity can be extended by adding more FUNCTIONS and to explain the concept of COMPOSITE FUNCTION.