Lesson 5.2 · Calculator
Hua's Classroom for Shanghai Maths — One Lesson One Exercise (English edition, pages 99–101).
Lesson Alignment
How this Shanghai Maths lesson connects to learning goals, Common Core, and Eureka Math.
Learning Objectives
Students will be able to:
- 01Match calculator keys to names. (Question 1)
- 02Enter keystroke sequences for +, −, ×. (Question 2)
- 03Form 2-digit × 2-digit with given digits (max/min product). (Question 3)
Common Core Standards
| Code | Standard (focus for this lesson) |
|---|---|
| 3.OA.D.8 | Multi-step calculations. |
| 4.NBT.B.5 | Multiply (check with calc). |
Eureka Math Correspondence
| Shanghai Maths | Focus | Eureka Math |
|---|---|---|
| Keys | ON/C, CE, = | G3–G4 |
| Keystrokes | Order matters | G3 |
Core Concepts
Match calculator keys; enter multi-step calculations correctly.
Calculator Keys
Power/All Clear, CE (clear entry), +, −, ×, ÷, =.
Keystroke Order
Enter numbers and operations in the same order as the number sentence.
Digit Challenges
Arrange four digits into two 2-digit factors for largest/smallest product.
Key Terms & Definitions (Reference)
Quick glossary for this lesson.
| Term | Definition |
|---|---|
| Clear entry (CE) | Clears the last number entered. |
| Keystroke | A button press on the calculator. |
Key Answers
Quick reference for this lesson’s exercise answers.
1. Match keys
Power/all clear ↔ on/c;\; M+ ↔ memory add;\; M− ↔ memory subtract;\; MR ↔ memory recall;\; CE ↔ clear entry;\; MC ↔ memory clear.
2. Multiple choice
(1) B turn off automatically;\; (2) D CE (clear the wrong entry);\; (3) B $3$ (display $312$).
3. Calculator
$1364$;\; $89168$;\; $1568$;\; $1338$.
4. Column + check
$763+337=1100$;\; $5000-697=4303$;\; $8457\times103=871\,071$;\; $1440\div120=12$;\; $9640\div48=200\,\mathrm{R}\,40$.
5. Largest / smallest products
- Digits $4,9,7,2$: largest $92\times74=6808$; smallest $27\times49=1323$.
- Digits $5,6,7,8$: largest $76\times85=6460$; smallest $57\times68=3876$.