In this activity, students will design and construct a working RCX or NXT music box in which LEGO mini-figures move while a song plays.

Students will learn to build with gears, and learn to program music.

Materials:
* RCX or NXT
* Assortment of LEGO pieces
* Gears
* Mini-figures
* Touch sensor
* Computers running LEGO programming software - NXT-g or ROBOLAB


Preparation & Setup:
* Set up computers running LEGO programming software.
* Arrange students in groups of two.
* Distribute necessary materials.


Procedure:

1. Have students build a music box using either an RCX or NXT.
2. The music box should consist of at least 1 sensor to turn it on a motor and gears.
3. Once students have built their music boxes, begin programming in ROBOLAB Inventor 4 or MINDSTORMS.
1. The music box should play when a sensor is triggered.
2. When the sensor is triggered the motor should turn gears that move the mini-figures and the music should play.
3. When the sensor is triggered again, the music box should stop the movement and music.