Sea Battle - Part 2 | 5th Class Lesson

Warning: Your screen size is quite small for viewing this. Rotate your device into landscape mode if you can.

1 Complete part 1 of this project
2 Add 'score' and 'lives' variables
3 Score a point
4 Lose a life
5 Game over
6 Extra Challenges
Quiz

1 - Complete part 1 of this project

In a separate lesson you should have completed part 1 of this project. Open your project in Scratch and continue to the next step in this lesson.

Or if you wish you can use this starter project that has part 1 completed.

https://scratch.mit.edu/projects/293643968/editor/

2 - Add 'score' and 'lives' variables

We need to create 2 more variables to store our score and lives. Create the following variables:

'score' will store our score
'lives' will store how many lives we have left

Once you've created these new variables we can set their values for the start of the game. Add in the two new blocks under the when I receive [start] block in the battleship sprite:




when I receive [start v]// add them under here
set [lives v] to (3)//start off with 3 lives
set [score v] to (0)//set score to 0 at the start
go to x (0) y (46)

Scratch: How to create a variable

In the Variables palette, create a new variable by clicking the 'Make a Variable' button.

Once you click this button a box will appear asking what you want to call your variable. Give it a name that reminds you what you will be using it for. For example, if you wanted to keep track of your score in a game, you would create a variable called 'score'.

👇 Mark your steps as done as you complete them.

+20 XP

3 - Score a point

Now let's add 1 to your score each time you hit a submarine.

In the submarine sprite, find the 'if touching my torpedo' code block and add the change [score] by 1 block into it.




if < touching (my torpedo v) > then // find this block
change [score v] by (1)// add this new block
wait (.2) seconds
delete this clone
end

Once you've added this block in, test that it works by playing the game. Each time you hit a submarine your score should go up by 1.

+10 XP

4 - Lose a life

Next add some code so you lose a life each time you get hit by an enemy torpedo.

Add the following new 'if then' group of blocks inside the forever block in the battleship sprite.



when I receive [start v]
go to x (0) y (46)
point in direction (90)
switch costume to (battleship v)
show
forever
if < key (right arrow v) pressed?> then
change x by (5)
end
if < key (left arrow v) pressed?> then
change x by (-5)
end

if < touching [enemy torpedo v] ? > then // add in these new blocks
change [lives v] by (-1)//lose a life
end

end

Test that this works before moving onto the next step.

Scratch: Using a tablet or iPad? Tap here for different controls

If you're using a tablet or iPad without a physical keyboard, you won't be able to use keyboard keys like the arrow keys in your project. Instead, we'll add simple on-screen buttons (using sprites) that you can tap to do the same things. This keeps your project working great! Just follow these steps wherever the lesson talks about pressing a key.

First, add a new sprite for your button:

Click the "Choose a Sprite" button in the bottom right.
Pick a simple shape, like an arrow or a circle. Make it small and place it on the screen where it's easy to tap, like the bottom corner.

Now, program your button sprite to make things happen when you tap it. Here's how it works for different situations:

Example 1: If the lesson uses a key to trigger an action on a specific sprite (like making something move, turn, or jump)

Instead of code like this on your target sprite:

when [left arrow v] key pressed change x by (-10) // or any action

Or this:

if < key [left arrow v] pressed? > then change x by (-10) // or any action end

Add this code to your new button sprite:

when this sprite clicked broadcast [do action v]

Then, on your target sprite, add this to receive the message:

when I receive [do action v] change x by (-10) // or any action

Tap the button on the screen, and the action will happen, just like pressing the key! Use a unique broadcast name for each different action or key.

Example 2: If the lesson uses a key to change a variable (like adding to a score or setting a value)

Instead of code like this:

when [space v] key pressed change [score v] by (1)

Or this:

if < key [space v] pressed? > then change [score v] by (1) end

Add a new button sprite. Then, put this code on the button sprite:

when this sprite clicked change [score v] by (1)

(If the variable is "for this sprite only," make sure it's set to "for all sprites" so the button can change it.)

Tap the button, and the variable changes, no message needed since it's something shared!

+20 XP

123learn · Online learning platform

Unlock the full learning experience

You're previewing this lesson. Get full access to this lesson and hundreds more — each one ready to teach, with interactive activities, printable resources and pupil progress tracking built in.

Hundreds of curriculum-aligned lessons

Interactive activities in every lesson

Printable resources & progress tracking

Get started

Copyright Notice
This lesson is copyright of Coding Ireland 2017 - 2026. Unauthorised use, copying or distribution is not allowed.

Scratch is developed by the Lifelong Kindergarten Group at the MIT Media Lab. It is available for free at https://scratch.mit.edu

Sea Battle - Part 2

Teacher Class Feed

1 - Complete part 1 of this project

2 - Add 'score' and 'lives' variables

3 - Score a point

4 - Lose a life

Unlock the full learning experience

XP