## Pre-Lesson Preparation

Learners will need to have a Marty per group to play the Marty Ship game: each group will control their Marty without seeing where they go, choosing a horizontal and vertical movement - using positive forward, backward, left and right movements. The group that is watching where Marty moves will need to correct them after each new movement due to Marty's interaction with a real-world environment.

The actual code needed for this lesson is minimal. The core learning is in mathematics.

## Warm-Up

Share with learners the objectives and success criteria for the day's lesson, from slide 2 of the presentation in the educator resource section; perhaps display this before the lesson starts and keep it displayed until another slide is needed.

Ask learners if any of them have heard of the game Battleships. If there are those that have not, play this short clip on YouTube, which is available by clicking here or by using the presentation on slide 3.

Distribute the10 x 10 grids which are available in the learner resources. There are two varieties of grids available, depending on if you are using grid references, which relate to the location of a space, or grid coordinates, which relate to where the horizontal and vertical lines overlap. (As just noted, this lesson is applicable to both grid coordinates and grid references. For ease of reading, we are only using the word coordinates from now on.) Have learners draw ships that either take up multiple spaces or encompass multiple intersections in a straight line. Give learners the opportunity to place 3 'ships', each with multiple spaces, and limit play between partners to about 10 minutes; it could take a long time to sink all three ships.

Click here if you haven't played Battleships before and go down to method 3.

Rather than having two grids per player, it is possible to use one sheet per person by having the player's guess marked with an X on the grid (using different colors for a hit and a miss) and the opponent's guess marked with an O.

## Get Learning

Following on from the game, where learners placed items at and guessed coordinates, learners will now need to think about moving between them. Have learners record several coordinates in the workbook, each from a different location a ship covered in the game. Have learners watch slide 4 or 5 from the presentation to see how we can find out how far it is from one coordinate to another. The workbook has space for 6 locations but this many movements does not need to be completed.

- slide 4 uses a grid coordinate format
- slide 5 uses a grid reference format
- please delete the slide you do not need

Have learners identify the movement between different coordinates on their grids, called translations. Then, challenge learners with their partner to see if they can each find the new coordinates from a given first coordinate after only hearing the directions to get from one to the other.

## Time for Practice

Tell learners that they are going to guide Marty on another team's game board to try and sink their Marty Ships. Watch the video that was on slide 6, but should now be on slide 5, to see examples of Marty in action trying to sink another teams ships.

## Click to see the process for play:

Groups need to sit near each other with a barrier blocking each group from seeing their Marty.

- Groups need to create a grid. It is recommended that each grid line be spaced at least one inch, or 25 mm, apart and more would be better. The reason for this distance is that that is the length of one of Marty's steps. If you choose to make the grid 2 inches x 2 inches (5cm x 5cm), each square side will require two steps. Using grid paper would significantly reduced the challenge in creating this but there are instructions for learners in the
- Groups will need three different colored pencils
- one color is for their own Marty Ships,
- one will be for the opposing team's shots
- one will be for their own shots, perhaps marking x for hit and o for miss

- Groups choose 3 or 4 places for a Marty ships and mark them on their grid with an x.
- Groups will place an opposing group's Marty on their (0, 0) point or (A,0) space. Marty's forward will be parallel to the y-axis and sidestep right will be parallel to the x-axis.
- One group will go first and will call out a coordinate where Marty thinks a ship is hiding, and with verbalize the movement required to get there:
- starting at (0,0) / (A,0)
- one group will say, ""(3,4) / (C,4)
- "Marty will go three right and four forward", the group will then program to do this movement"
- if it is a 'hit' the other group will say, "hit," if it is a miss, they will say, "miss"
- both groups should mark the location with the pre-chosen colors

- The guessing group should record the initial location, the movement required and the new guess. There is a table in the workbook to accommodate this.
- The group with the Marty that moved should reposition Marty in case they did not walk in an exactly straight line, which is common for walking robots
- Change over so the other group has an opportunity to guess and move
- Continue the game in the available time

## Cool Down

Bring learners back together after a fair amount of time has been given for play. Have learners share any strategies they used to try and find the other Marty Ships. Ask learners how accurate they were with their instruction for where Marty had to go to reach a location.

Suggested questions you might ask:

- Which value do you say first when giving a coordinate?
- Were any directions more challenging than others, why or why not?
- Can you think of any other ways to reinforce location changes using horizontal and vertical movement?

Carry out any end of lesson routines.