Orient to the shared workbook: sheet map, evidence blocks, and success criteria
The Shared Workbook Map
Download the shared rehearsal workbook below. Every student in this class is using the same data. Your job today is to understand what each sheet is supposed to prove, not just what it contains.
Download and open: unit07-lesson07-student.xlsx
This workbook uses the same shared dataset for every student. The teacher workbook is identical: unit07-lesson07-teacher.xlsx — use it to verify your structure after each section.
Step-by-step tutorial: unit07-lesson07-tutorial.md
A project workbook is not a random collection of sheets. Each one has a job in the evidence chain. Here is the structure you will rehearse today and reuse in the project:
ReadMe / Brief
Job: States the business problem, dataset source, and what this workbook will answer. An investor should understand the context in 30 seconds.
Inputs (BeginningInventory, Purchases, Sales)
Job: Holds the raw transaction data — beginning inventory layers, dated purchases with unit costs, and dated sales. This is the foundation. If inputs are wrong, everything downstream is wrong.
Valuation
Job: Calculates COGS and ending inventory for each method (FIFO, LIFO, Specific ID, Weighted Average). This is where the method logic lives. Each method block must show layer-by-layer assignment.
MethodCompare
Job: Side-by-side comparison of all four methods showing COGS, ending inventory, gross margin, turnover, and days-on-hand. This sheet makes the tradeoffs visible.
Checks
Job: Validation flags that catch problems before totals roll up: missing SKUs, negative/zero unit costs, GAFS mismatch, stale dates. Place these above KPI tiles so they are impossible to miss.
Dashboard
Job: KPI tiles and charts that update from structured Table references. An investor should see turnover, days-on-hand, gross margin, and method comparison at a glance.
Recommendation
Job: States the recommended method, cites exact workbook numbers as evidence, and names one risk or limitation. This is the payoff — every other sheet exists to support this claim.
Your rehearsal workbook is complete when ALL of the following are true:
- All four inventory methods calculated correctly (FIFO, LIFO, Specific ID, Weighted Average)
- COGS + Ending Inventory = GAFS for every method (checksum passes)
- MethodCompare sheet shows side-by-side results for all four methods
- Checks section flags at least: missing SKU, invalid unit cost, GAFS mismatch
- Dashboard shows turnover, days-on-hand, and gross margin for the selected method
- Recommendation sheet includes: claim, evidence (with specific numbers), and one risk
- No #N/A, #REF!, or #DIV/0! errors visible in any sheet
- Formulas documented in plain language near results
Today's goal: get as close to this standard as possible. You will refine further in the real project.