Scratch variable monsters maths mission

Quick answer

In Scratch, variable monsters are fun characters that help you learn about unknowns or missing numbers in maths. By using these monsters in a mission, you can practice solving problems like "If a monster has 5 apples and eats some, how many are left?" You learn to use variables to store and change numbers in your Scratch programs.

Learning outcome

By the end of this page, you will be able to use Scratch variable monsters to represent unknown numbers and solve simple maths problems with missing values.

• You can create a Scratch program with a variable monster that changes its number.
• You can solve problems where one number is missing using a variable monster.
• You can explain how variable monsters help you think about unknowns in maths.
• You can play a mini-mission to practice using variables with monsters.

Why this matters

Learning about variables helps you solve puzzles and problems in maths, like "What number am I thinking of?" or "How many more do I need?" In Scratch, variable monsters are a fun way to understand how numbers change and how we can use them to solve problems. This skill is helpful for all kinds of real-life maths, from counting your pocket money to sharing snacks with friends.

How it works

Variables are like boxes in Scratch where you can store numbers. A variable monster is a character in a Scratch program that holds a number. Here’s how you can use them:

1. Choose a monster – Pick a character in Scratch to be your variable monster.
2. Set a variable – Give your monster a number to start with, like 10 apples.
3. Change the number – Add or take away from the number using Scratch commands.
4. Find the unknown – Use the monster to help you figure out what number is missing in a problem.

Examples you can see

Let’s imagine your variable monster is a friendly dragon named Sparky. Sparky starts with 8 gems in his treasure chest. Then, he finds 3 more gems. How many gems does Sparky have now?

Step 1: Sparky starts with 8 gems.

Step 2: Use a Scratch command to add 3 gems to the variable.

Step 3: The variable now shows 11 gems.

So, Sparky has 11 gems in total.

Now, let’s try a problem with a missing number:

Sparky had some gems. He gave 4 to his friend and now has 6 gems left. How many gems did Sparky start with?

Step 1: Let’s say the variable starts with the unknown number, let’s call it X.

Step 2: Subtract 4 from X to show what he gave away.

Step 3: The result is 6 gems.

So, X – 4 = 6, which means X = 10.

Sparky started with 10 gems.

Try it as a mini adventure

Imagine you are on a maths mission with your variable monster! You must help your monster find the missing number in each puzzle. Here’s your mission:

Adventure 1: Your monster has 7 coins. It spends 3 coins on a snack. How many coins does it have left?

Adventure 2: Your monster had some cookies. It ate 5 cookies and now has 9 cookies left. How many cookies did it start with?

Adventure 3: Your monster collects 6 stickers. Then it gets 4 more stickers. How many stickers does it have now?

Adventure 4: Your monster had 12 stickers. It gave away some stickers and now has 7. How many did it give away?

Adventure 5: Your monster starts with 5 stars. It gains 8 more stars. How many stars does it have now?

Common mistakes

• Mistake: Forgetting to set the variable to a starting number before changing it.
• Why it happens: Kids might think the variable is already filled with a number.
• Fix: Always start with a command like "set variable to 5" before adding or subtracting.

• Mistake: Mixing up what the variable is supposed to show.
• Why it happens: Kids might get confused between what they're adding and what they're trying to find.
• Fix: Draw a simple picture or write a sentence like "Sparky had X cookies, ate 3, now has 6" to help understand.

• Mistake: Thinking that if a monster has 10 coins and spends 3, it now has 13 coins.
• Why it happens: Kids might confuse addition and subtraction.
• Fix: Use counters or fingers to show that taking away means less, not more.

Parent and carer guide

Help your child by:

• Playing along with the variable monster mission using your own Scratch program or drawings.
• Encouraging them to explain their thinking, like "How did you figure out how many coins Sparky started with?"
• Using everyday situations to practice variables, like "You had 5 toys, and you lost 2. How many do you have now?"
• Not worrying if they make mistakes – that's how they learn!
• Reinforcing that variables are just like boxes that hold numbers, and we can change what’s inside them.

Try this with your child: Ask them to create a variable monster of their own and tell you a story about how many items it has. Then, challenge them to change the number by adding or taking away items. This builds their understanding of how variables work.

Practice questions

1. Monster starts with 9 gems and finds 2 more. How many gems does it have now?
2. Monster had 15 cookies. It ate 6 cookies. How many cookies are left?
3. Monster had some stickers. It gave away 5 and now has 7. How many did it start with?
4. Monster collects 4 stars and then gets 3 more. How many stars does it have?
5. Monster had 12 candies. It gave away 4 candies. How many candies does it have now?

Answers:

1. 11 gems
2. 9 cookies
3. 12 stickers
4. 7 stars
5. 8 candies

FAQ

What is a variable in Scratch?

A variable in Scratch is like a box where you can store a number. You can change the number in the box as your program runs.

Why use monsters to learn about variables?

Monsters make learning variables fun and visual. They help children imagine numbers changing and help them understand what unknowns look like in a problem.

Can I use any character as a variable monster?

Yes! You can choose any character in Scratch to be your variable monster. It could be a dragon, a cat, a robot, or even a pizza!

How do I create a variable in Scratch?

In Scratch, click on the “Variables” category, then click “Make a Variable.” Name it something like “Coins” or “Gems,” and then you can use it in your program.

What if I don’t know how to use Scratch?

That’s okay! You can start with simple programs, or even draw your variable monster on paper and use counters or stickers to show how numbers change. The idea is to understand the concept, not to master Scratch right away.