Monday
Welcome to Grade 2, Crew!
The crew has a fleet of test ships.
Each ship flies with an auto-pilot program.
Test flights always stay over safe, open ground.
But something strange keeps happening.
On every flight, the ship drops down low.
It drops at the very same spot, every time.
Rocket thinks the auto-pilot has a bug.
Raven wants to find it. So do you!
- Read each little program.
- Tap the answer.
The same drop, every time
Nova scans the auto-pilot program.
Nova beeps. I found a pattern!
The drop happens near a memory box.
What is a memory box? Let us find out.
Nova has memory boxes
A memory box has a name tag.
It holds one number.
Coders call a memory box a variable.
Look inside the box
The name tag says height.
The number inside is 3.
So the height box holds 3.
set height to 3 say height land
Set puts a number in the box.
Say makes Nova peek and say it.
Nova says 3, not the word height!
- Read the program lines.
- Tap what the box holds.
Now you build an auto-pilot test.
Nova must say 2, then land.
Fill the box before Nova peeks!
- Read each card.
- Make Nova say 2, then land.
| program | Nova says 3? |
|---|---|
| set height to 3, say height | ? |
| set height to 5, say height | ? |
| say height, set height to 3 | ? |
| set speed to 3, say speed | ? |
You met the memory box!
A memory box has a name.
It holds one number.
Set fills it. Say peeks inside.
Great work, Crew!