Class 3 · Topic 2
Addition & Subtraction
Step 1 · Learn
Read the ideas
- 🐇🔒
The Hopping Map
Hop the hundreds, tens, then ones.
- 💥🔒
Number Smashers
Add the hundreds, tens and ones, then join them.
- ➕🔒
Add It Up
Carry the extra when a column overflows.
- ➖🔒
Take It Away
Trade 1 ten for 10 ones when the column is short.
- 🎰🔒
Missing Numbers
Start at the output and reverse each step.
- 🔮🔒
Estimating Sums & Differences
296 + 405 is about 300 + 400 = 700.
- 🤔🔒
Is It Reasonable?
Estimate first, then trust it or doubt it.
Step 2 · Practice
Try the quests
Step 3 · Boss Battle
Beat the boss
🛡️ 🛡️ 🛡️ 3 shields — lose all → 60-second cooldown
Round 1
A factory made 3,486 toys in the morning…
🔒Round 2
A stadium holds 8,000 fans. 3,463 seats are…
🔒Round 3
A machine on the vault wall shows: number →…
🔒Round 4
The vault lock opens to the estimate of…
🔒Round 5
A guard's ledger claims 3,400 + 2,600 = 900.
🔒Round 6
The gate lock sits on 348. You must hop it…
🔒Round 7
The reactor needs 356 + 275 units. Smash…
🔒