Give a presentation and then, based on the information provided there, introduce children to the subject, roles, and communication types.
Divide your class into 7 teams. Provide each team one worksheet - it contains one task to be coded (greeting, goodbye, warning of danger, call for help, call to action, end of action, thanks).
The children's task is to complete the worksheets by creating a coded message conveying a specific piece of information (as assigned). Given that children are using the Photon Badge interface, they can use the symbols for changing colors and sounds. If necessary, ask them to check in the application which symbols are available.
Ask children to use magnets to attach their worksheets with codes to the classroom board. Analyze results from all teams. Ask children to analyze their codes again and make any necessary changes/corrections.
If two groups were working on the same message, choose together which code sequence will be used later during the class.
Then, move on to acting out the scene with the robots. Read an adventure story about the robots that includes actions to perform (coded messages). The children's task is to act out this scene by programming the robots accordingly. Assign roles to the robots (robot 1 is the one who is invited to talk, and robot 2 accepts the invitation). You should ask the teams to name their robots. The children act out the scenes one by one.
NOTE! If you have more than two robots, you might want to modify the scenes so that all teams communicate simultaneously (example below).