My 5th grader keeps repeating these two
Ask
My 5th grader keeps repeating these two mistakes on his homework every week:
1) Adding fractions: 1/3 + 1/4 = 2/7 (he just adds the numerators and denominators together).
2) Subtracting across zeros: 400 - 167 = 333 (he forgets how borrowing across double zeros works).
We live in Vancouver (America/Vancouver). Can you log these two mistake cards into our notebook, clustered by root cause, and set a daily evening reminder at 19:00 for us to review whichever cards are due?
Answer
I'll log both cards clustered by root cause (they're two different error types, so two cards), and set the19:00 reminder. Let me first check the family profile, the capture reference, and today's due state in parallel.
No members are tagged, but the user gave the timezone directly. The notebook is empty — no cards due today. Let me read the disk schema and append the two cards.
Let me compute Vancouver's local date (since the platform clock is Shanghai-based, and Vancouver is 15 hours behind).
Vancouver local date is 2026-09-15. Now appending the two cards — they have different root causes, so two cards, not one merged card.
Both cards logged (2 added, 0 duplicates). Now setting the daily 19:00 Vancouver reminder.
Both cards are in your notebook, and the daily review reminder is set. The two errors come from different root causes, so they're two separate cards — one card per cause is the rule, otherwise the pile grows back to a copy of the homework.
**Card 1 — fractions**
- Prompt: 1/3 + 1/4
- Wrong move: 2/7 — added 1+1=2 on top and 3+4=7 on bottom
- epair: Find a common denominator (LCD = 12). 1/3 = 4/12, 1/4 = 3/12, then 4/12 + 3/12 = 7/12. Add numerators only after rewriting both pieces.
- Same-type to try later: 1/2 + 1/3 = ?
- Tag: fractions
**Card 2 — borrowing across zeros**
- Prompt: 400 − 167
- Wrong move: 333 — borrowing across the double zeros didn't work
- epair: Borrow 1 hundred as 10 tens: 400 → 3 hundreds, 9 tens, 10 ones. Then 10−7 = 3, 9−6 = 3, 3−1 = 2 → 233.
- Same-type to try later: 500 − 238 = ?
- Tag: borrowing
The cards live on your personal disk. When you'd like a printable wall sheet, just ask and I'll export it.
**Daily reminder:** scheduled at 19:00 America/Vancouver. The system staggers it a few minutes for load balancing, so it actually fires at **19:12 every evening**, starting tonight (2026-09-15 Vancouver time). It will prompt your son to try the day's due cards from memory first, then reveal the repair. To stop it, just tell me "stop the reminder" and I'll disable it.
A small note on scope: these cards store the prompt, the wrong move, and the repair — they don't store *why* the LCD method or the borrow chain works. If your son wants to talk through the reasoning behind either, that's a separate teaching conversation we can pick up later.