Free / Grades 8-9, with signed-number support
Cash Records Lab
When two balances disagree, what evidence tells us which record needs to change?
4 flexible sessions / about 165 minutes including practice / cash reconciliation, source checking and evidence reports
Suggested rhythm: two sessions a week for two weeks. First compare timing and copying errors; then investigate a bank error and revisit an earlier case. Take longer when useful.
Reading, watching and paper activities are free. Parents and instructors can save a collection; scheduling it for a student requires Plus or Lifetime. No upload is required.
Before you begin
Add and subtract signed whole numbers. Know that Cash is an asset: debits increase it and credits decrease it. Review the linked lessons before using journal-entry language.
Fictional records only. No real money, banking access or personal financial records are needed. Amounts are invented dollars, not S3U coins. Do not upload statements or contact a bank. This paper model excludes tax, loans and returned payments; it is learning practice, not financial advice.
Materials
- 4 sheets per learner: Session journals
Print the journals or copy their headings into a notebook.
- 2 sheets per learner: First explanation and final report
Keep both versions on notebook or scrap pages.
- 1 per learner: Pencil
Speak, dictate or use an accessible writing tool.
- 1 shared, optional: Calculator
Use written arithmetic after explaining each adjustment.
- 1 shared: Browser or printed pages
Read transcripts and supplied records together. Separate worksheet printing is optional.
Choose the support that fits
- More support: label two columns BANK and BOOKS. For each item, say where it is already recorded before choosing a sign.
- More challenge: make two supported errors cancel in a closing total, then explain why both still need correction.
- Access options: give a private spoken report or dictate the tables. Color, handwriting, uploading and public presentation are not required.
What good evidence looks like
- Identify the period and source for each difference.
- Separate timing items from missing book entries and errors.
- Correct only the unsupported difference, with the right sign.
- Keep original records and explain what changed.
- Do not double-count cleared items or invent entries to force a match.
These are discussion criteria, not a new automatic score. Existing lesson and worksheet records keep their own subjects. Checking off a planned task does not demonstrate mastery or add a second grade.
Session 1 / about 40 minutes
Give each difference a home
Goal: Separate bank timing adjustments from book entries and explain why the same transaction must not be recorded twice.
Preparation / about 8 minutes of adult support: Use journal 1 and a separate first-explanation sheet. Read BANK and BOOKS aloud; both describe the same fictional club cash, not two pots of money.
The club books are its own cash record. A bank statement is another record of that account. At a cutoff date, a deposit already in the books may not yet appear at the bank. Add that deposit on the bank side of the comparison, not to the books again. An uncleared check works the other way: subtract it on the bank side. For a separate example, bank 500 plus deposit 70 minus check 40 gives 530. Books 536 plus missing interest 4 minus missing fee 10 also gives 530. Only the missing interest and fee need new book entries. Two equal answers are reassuring, but the calculator has not interviewed the receipts.
For each adjustment, ask: where is this already recorded? What would happen if we added the deposit to both sides?
- Reconcile cash records / about 10 minutes
- Reconcile Two Cash Records / about 10 minutes
- Explain Case A at October 31 / about 20 minutes
Fun fact: In the worked example, the two starting balances differ by 36, yet neither is simply replaced by the other. The explained adjustments bring both to 530.
S3U / Cash Records Lab / Journal 1 of 4
Case A: two records, one account
At October 31, BANK is 800 and BOOKS is 872. Deposit D18 of 120 and check C17 of 60 are already correctly in BOOKS but not BANK. BANK includes interest I1 of 8 and fee F1 of 20, neither yet in BOOKS. No other differences are known. All amounts are invented dollars.
| Record to explain | My calculation and evidence |
|---|---|
| BANK: D18 and C17 adjustments | |
| BOOKS: I1 and F1 adjustments | |
| Compare the adjusted balances | |
| New book entries: Cash debit or credit? |
Why do D18 and C17 need no new book entry? Label the other account for each interest/fee entry.
Keep a first explanation: does a matching total alone prove that all source records are correct?
Session 2 / about 40 minutes
Repair the difference, not the whole payment
Goal: Use a source payment to correct a copied book amount in either direction without recording the payment again.
Preparation / about 8 minutes of adult support: Use journal 2. This is separate Case B, not a new transaction in Case A. Keep the original amount beside its supported correction.
Suppose a supplies payment was 48, but the books subtracted only 18. Cash is 30 too high. Subtract another 30, not another 48. In a different example, a payment of 48 was copied as 78; Cash is 30 too low, so add 30 back. A correction is the missing change between the recorded amount and the source. If the wrong original entry used Supplies expense, the correcting entry uses that same account on the opposite side of Cash. Preserve the source and the old entry. An eraser is not an audit trail.
Ask whether too much or too little cash was subtracted before calculating. Why does paying less than the copied amount make the correction positive?
- Correct cash record errors / about 10 minutes
- Reconciliation: A Payment Recorded Too Small / about 10 minutes
- Repair Case B with a source trail / about 20 minutes
Fun fact: The same true payment of 48 needs opposite corrections when copied as 18 or 78. The source amount alone does not tell us the correction.
S3U / Cash Records Lab / Journal 2 of 4
Case B: the payment was smaller
At November 30, BANK is 620 and BOOKS is 560. Deposit D2 of 50 and outstanding check C2 of 80 are correctly in BOOKS only. BANK includes missing interest 6 and fee 12. Source P4 and BANK show a supplies expense payment of 72; BOOKS debited Supplies expense and credited Cash for 108. These are all the differences.
| Case B check | My calculation and reason |
|---|---|
| P4: original, source and Cash correction | |
| Adjusted BANK | |
| Adjusted BOOKS | |
| P4 correcting entry: debit and credit |
Explain why entering the entire 72 again would be wrong. Include the missing interest and fee entries.
Separate challenge: a payment of 84 was copied as 48. What Cash correction is needed? Do not add it to Case B.
Session 3 / about 40 minutes
Require evidence for a bank error
Goal: Distinguish a confirmed bank-only error from a club book correction, and retain an unexplained difference when evidence is missing.
Preparation / about 8 minutes of adult support: Use journal 3 and keep the explanation on paper. The supplied confirmation is fictional evidence; nobody should contact an actual bank.
A strange number is not enough to call something a bank error. In a separate example, the bank confirms it charged this account 40 for another account. Bank 700 therefore needs plus 40 to reverse the wrong deduction; deposit 50 and outstanding check 90 then give 700. Books 708 plus interest 2 minus fee 10 also gives 700. The unrelated charge was never in the books, so it creates no club expense or book correction. If the confirmation is absent, keep the difference unresolved while requesting relevant evidence in your report. Matching numbers cannot manufacture a missing document.
What source supports reversing the charge? Why would adding a made-up club expense hide the problem rather than explain it?
- Reconciliation: Find Which Record Is Wrong / about 10 minutes
- Check the Case C confirmation / about 15 minutes
- Reconcile Case C without an invented entry / about 15 minutes
Fun fact: A wrongly deducted amount is added back, while a wrongly added amount must be subtracted. Reversing an error means undoing its direction.
S3U / Cash Records Lab / Journal 3 of 4
Case C: an extra credit is not income
At November 30, BANK is 960 and BOOKS is 905. Deposit D3 of 45 and outstanding check C3 of 75 are correctly in BOOKS only. Interest 5 and fee 10 are in BANK only. Fictional confirmation E3 says BANK mistakenly added 30 belonging to a different account. That 30 is not in BOOKS. No other differences are supplied.
| Evidence decision | My adjustment and explanation |
|---|---|
| E3: side and sign of correction | |
| Adjusted BANK with E3 | |
| Adjusted BOOKS; required new entries | |
| Without E3: known BANK adjustments only |
Why must we not treat the unrelated 30 as club income or put it into the books?
If E3 were unavailable, compare the known adjusted balances and write a request for evidence, not a balancing entry.
Session 4 / about 45 minutes
Follow Case A into the next month
Goal: Carry corrected records forward, avoid counting cleared timing items twice and revise a final report using explicit evidence.
Preparation / about 9 minutes of adult support: Bring journal 1 and the first explanation. Use journal 4 and a final-report sheet. Session 4 continues Case A only; Cases B and C never enter its balances.
An outstanding item belongs on the comparison only while it remains outstanding at that cutoff. Suppose last month ended with corrected Cash of 100. This month the books correctly add new receipts 40 and subtract new payments 25, reaching 115. Last month's check of 20 now clears at the bank; the books already included it before the opening 100. Subtracting it again would falsely reduce 115 to 95. Check identifiers and dates, not just amounts. Your final report should preserve corrections, explain unresolved questions and name its evidence limits. A balanced report is not permission to stamp everything PERFECT in enormous letters.
Which opening balance should the next month use? How can a bank transaction be new on this statement without being new in the books?
- Continue Case A into November / about 20 minutes
- Create my cash evidence report / about 15 minutes
- Revisit my first explanation / about 10 minutes
Fun fact: In the worked example, subtracting an old 20 again creates a false shortage of 20. A correct arithmetic operation can still be the wrong accounting step.
S3U / Cash Records Lab / Journal 4 of 4
My report across two cutoffs
Continue Case A using its corrected October Cash from journal 1. November BOOKS correctly add new receipts 240 and subtract new payments 190. At November 30 BANK is 875. New deposit D28 of 80 and check C27 of 55 are in BOOKS only; interest I2 of 4 and fee F2 of 14 are in BANK only. Old D18 and C17 both cleared correctly in November. No other differences are known.
| November report | My calculation and evidence |
|---|---|
| Opening corrected Cash; November BOOKS | |
| Adjusted November BANK | |
| Adjusted November BOOKS and new entries | |
| D18 and C17: count again or not? |
A draft subtracts old C17 again. Explain the error and the amount by which its ending book balance is too low.
If BANK were 874 with all other evidence unchanged, what difference would remain? Preserve uncertainty and revise your first explanation.
What changed in your explanation?
Show your evidence, explain one revision, and choose a question to investigate next. You can keep everything on paper.
Optional: record actual offline learning in Learning Records. Keep reported minutes separate from website time. For an assigned pack, use your existing daily tasks; this page does not award additional completion credit.