Each group needs:

• 1 computer ball mouse

Note: Computer ball mice can be purchased online at Amazon, Ebay, lessEMF or other resellers for ~$10 each; ball mice, not optical mice, must be used. The mouse should have a USB connection; adapters can be purchased online at Tiger Direct. Tracking mice, with a ball mechanism (not an optical mechanism), will suffice.

• screwdriver
• duct tape
• laptop with an on-screen pixel ruler and drawing program
• ruler
• paper
• calculator
• 1 wide-tipped marker
• Rotary Encoders Pre-Activity Worksheet, one per student
• Encoder Worksheet, one per student
• Results and Analysis Worksheet, one per student

For the LEGO MINDSTORMS EV3 rotary encoder demonstration setup: (Note: In advance of the activity, prepare one LEGO MINDSTORMS EV3 rotary encoder for each group.)

• LEGO MINDSTORMS EV3 robot, such as EV3 Core Set (5003400) at https://education.lego.com/en-us/products/lego-mindstorms-education-ev3-core-set/5003400#lego-mindstorms-education-ev3
• LEGO MINDSTORMS color sensor (in addition to the one provided in the Core Set), available at https://shop.lego.com/en-US/EV3-Color-Sensor-45506
• masking tape
• scissors
• box cutter
• 2-3 sheets of white copy/drawing paper
• manila folder
• Rotary Encoder Building Instructions
• 1 printed copy of Rotary Encoder Cutout
• Rotary Encoder Display Program

Note: This activity can also be conducted with the older (and no longer sold) LEGO MINDSTORMS NXT set instead of EV3; see below for those supplies:

• LEGO MINDSTORMS NXT robot, such as the NXT Base Set
• LEGO MINDSTORMS Light Sensor (in addition to the one provided in the Base Set)
• Rotary Encoder Building NXT Instructions