They know what a touch sensor looks like and what input port it is
on.
They can program the RCX to respond to input from the touch sensor.
Today they make the bot do a song and dance in responds to touch and
light.
Thanks to our number 1 helper for some setting up of the computer.
They connected the outputs to work correctly
and also used the light sensor.
On their own this group did a program with 5 steps that each used a
sensor.