Lesson 3.2 · Year, month and day (2)
Hua's Classroom for Shanghai Maths — One Lesson One Exercise (English edition, pages 45–48).
Lesson Alignment
How this Shanghai Maths lesson connects to learning goals, Common Core, and Eureka Math.
Learning Objectives
Students will be able to:
- 01Name big and small months and their day counts. (Question 1)
- 02Solve clock/time interval problems linked to dates.
- 03Judge true/false statements about months and quarters.
- 04Solve calendar sum and duration enhancement problems.
Common Core Standards
| Code | Standard (focus for this lesson) |
|---|---|
| 3.MD.A.1 | Time intervals in minutes. |
| 3.OA.D.8 | Multi-step problems. |
| 3.NBT.A.2 | *(related)* Add/subtract for date sums. |
Eureka Math Correspondence
| Shanghai Maths | Focus | Eureka Math |
|---|---|---|
| Months | Big / small | Calendar fluency |
| Elapsed time | Minutes / hours | G3 M2 |
Core Concepts
Big months vs small months, date/time calculations, and careful calendar reasoning.
Big & Small Months
- Big months have 31 days.
- Small months have 30 days (February is special: 28/29).
- A year has 7 big months and 5 small months (counting February as small).
Month Rhyme (memory aid)
“Thirty days hath September, April, June and November…” — use the book’s rhyme version (La / Dong months) as a memory tool.
Time Calculations
- Leave-home time: gate close time − walking time (e.g. 15 minutes earlier).
- Match end: start $19{:}30$ + $155$ minutes → convert hours/minutes.
- Consecutive calendar dates whose sum is given (tear-off pages).
True / False Traps
- Not all odd months are big (e.g. February is month 2).
- Neighbouring months of a 30-day month are not always both 31.
- Quarters: third quarter = Jul–Sep (92 days in a common year).
Key Terms & Definitions (Reference)
Quick glossary for this lesson.
| Term | Definition |
|---|---|
| Big month | Month with 31 days. |
| Small month | Month with 30 days (Feb special). |
| Quarter | One of four 3-month parts of a year. |
| Elapsed time | How much time passes between two clock times. |
Key Answers
Quick reference for this lesson’s exercise answers.
1. 12 months; Jul & Aug / Dec & Jan consecutive 31-day pairs; big (31): Jan, Mar, May, Jul, Aug, Oct, Dec; small (30): Apr, Jun, Sep, Nov.
2–3. Common 365 / Feb 28; leap 366 / Feb 29; Q1 = 90 or 91 days.
4. Ticket 13:22 → 1:22 pm; leave by 1:07 pm; valid 9 May 2019.
5. Birth-year days — student-specific.
6. 1844, 1852; 1916, 1928, 1932; leap ✓2008 ✓2020. Centuries: 800, 1600; leap ✓2400.
7. La = Dec; Dong = Nov.
8. T/F: ✗ ✗ ✓ ✓ ✗ ✗
9. 36 months; 21 days; 2 days; 60 min = 3600 s.
10–13. Yogurt after 19 Oct; days-alive student-specific; calendar sum 24 → home 9th; match ends 22:05.