Warm up

Ask learners who has ever played a reaction game, maybe Whack-a-Mole or Dobble. For those that have, ask them to describe to those who have not, the purpose of the game and how it works. Share with learners the first three slides from the presentations, the title, objectives and success criteria.

If you have reaction type games, feel free to show them, If not, there are three slides in the presentation, the first of these is Dobble, a reaction card card, the second is a math app for a table or phone and the third is a physical setup with a micro:bit that uses code to create the reaction game. Feel free to show or delete the slides as you wish, they are all set to begin at a place that is showing the game, or app, in action, skipping any superfluous information.

Show learners a video of Marty 'judging' two players interacting with a micro:bit. Let them see the variety of controls that are being used and how Marty responds to each of the 'reaction rounds'. The video on the presentation does not include the scoreboard. The set up of variables is described in the teacher's guide. Learners can use their workbooks to determine what conditions are necessary to properly develop a game that return the results of who was faster.

Get Learning

The following are ideas for questions and responses before coding starts,

Educator: How did players know when they had to press the button on the micro:bit?
Learners: There was an icon on the micro:bit display.
The micro:bit flashed a picture.
E: How do we check who was fastest?
L: We could use a conditional / if statement to trigger a response, when the faster person responds.
We could use a wait block to act as soon as someone presses a button.
We could use a loop, with a conditional statement, to constantly check if a button is pressed.
We could use the micro:bit command block to act as soon as a button is pressed.
E: How can we keep score?
L: We could create a variable that stores each player's score.
We could create functions for what happens when a player is faster, each function would increase the appropriate variable.
E: How could we ensure that the game continues until someone wins.
L: We need to go back to the main code without reseting the score.
We need to have the reaction part of the code happen again.
We need to end the game when the goal is reached.
E: Is there a way we can display scores?
L: We could use variables.
We could change the values for the variables depending on who is faster for each round.

Have learners complete the activity that checks understanding of vocabulary that will support today's activity.

In case you want a reminder for preparing Marty for work with the micro:bit, share the videos below, with learners. Feel free to delete the slides and show learners how to do these steps, or set up the devices before the lesson. If you choose not to use the videos in the presentation, you should delete the appropriate slides.

The video below is in the presention, following the video is a graphic displaying the code that was used for this. It would be good to discuss what the micro:bit blocks are doing and why that isn't exactly what we want to happen in the game: Marty moves toward the person that was fastest and then moves toward the other person. How can we make Marty only go one way? Hopefully, learners will suggest a conditional statement: if button A is first, do action A, else if button B is first, do action B. The challenge arises as to where to arrange that. The code example, in the teacher guide, uses functions but there might be other ways to do it. Suggestions are included in the teacher guide.

Given that learners will be familiar with the micro:bit event blocks, they should come to the conclusion that using micro:bit events is not the best way forward unless they feel confident that they know who was fastest depending on the direction Marty first moves. Take time to comment that this is not an efficient solution and it can be ambiguous, which may lead to arguments.

Remind learners about conditional statements, if they were not suggested. Perhaps a question like how do we trigger an action based on a particular input? If we did this, could we somehow ensure that the trigger will only respond to the faster of the players?

Give learners time to talk about how to plan a conditional statement.

Time for Practice

Give learners plenty of time to develop their code for the reaction game. At an appropriate time, ask the whole class how they are going to decide who wins? Have them think back to when Marty danced after the first video: how could we store something to keep track of the score for the two players? Learners will hopefully suggest using a variable. If they don't, ask what do you call the element of code that can store a value and can change depending on running code. That should be enough to remind learners of variable. Use other questions to guide learners in case that question isn't enough. When learners agree that variables are necessary, for a score, remind them about the helpfulness of useful variable names: x, y and z do not do much to support someone, who did not write the code, who is trying to figure out the purpose of the variables.

Take time to walk around the classroom commenting on work accomplished and asking supportive questions.

Cool Down

Bring learners back together to discuss the challenges they faced and overcame. Have groups model their creations and explain what is happening, when. Encourage other groups to ask questions to deepen the understanding of the processes.

Take time to have group code displayed to the class, encourage observational questions from peers.

Suggested questions you might ask:

• How did you decide how to record the score?
• What route did you take to only accepting the faster response?
• How did you decide what the winning value was going to be?

Carry out any end of lesson routines.

Log off devices and clear everything away.