Supply Chain LabTeaching guide · SCOPE 2Supply Chain LabTeaching guide · SCOPE 2One product, one city, four shops fighting over the same customers - and a chain behind them that always arrives a round late. This page explains the whole game with one worked example, then tells you exactly which buttons you press. If you read only one thing, read the six numbered steps below: that is the game.
← Back to SCOPE 2Read this aloud in class if you like. Every number below is invented for the story; the shape is exactly what the software does each round.
You stand up and say: “This round Melbourne wants 2,200 cans of VOLT.” That number changes every round, and only you know the whole series in advance.
There are 4 retailers in the class. They each type one price into their phone and nobody else sees it. A can costs the shop $8.00 landed, so the price they choose is their margin.
| Shop | Sealed price | Cost per can | Margin per can |
|---|---|---|---|
| Sara | $9.50 | $8.00 | $1.50 - cheapest |
| Shop 3 | $11.00 | $8.00 | $3.00 |
| Ali | $12.00 | $8.00 | $4.00 |
| Shop 4 | $13.00 | $8.00 | $5.00 - dearest |
The demand is split by price. Sara, being cheapest, pulls the biggest slice - about 780 cans. Ali, being dear, is capped at a small guaranteed floor share - about 180 cans. Nobody is wiped out, but the gap is brutal.
But stock is real. If Sara only has 400 cans on the shelf, she sells 400 and the rest of her crowd cascades to the next-cheapest shop that still has stock. Winning the price war with an empty shelf hands your customers to your rival for free.
Sara orders 800 cans from her wholesaler. They do not appear now. They arrive next round, and she pays on delivery.
He has 500 cans in the warehouse and two shops asking for 800 each. There is no formula - it is his call. Then he places his own order with the distributor, who does the same thing to him, and so on up to the supplier. Every tier is a human making the same squeeze.
Anything still on the shelf is charged holding every single round - 32c per can at the shop, less as you go upstream. At the end of the game, unsold stock is written off. After 18 rounds the chain with the highest total profit wins.
The trap. Cheap wins volume but thin margin. Dear protects margin but starves. The winner is usually somewhere in the middle. And because stock takes a round to arrive, everyone over-orders after a good week - that is the bullwhip, appearing on its own, without you mentioning it once.
You are not bidding against the market. You are bidding against the three people in this room who are also guessing what you will do.
VOLT and the $8.00 can are the story. On screen the game uses a fixed price ladder - Supplier sells $2.50, Manufacturer $4.00, Distributor $5.50, Wholesaler $7.00 - and retailers may bid anything up to $25.00 (the default ceiling, which you can change). Only retailers choose a price; everyone upstream chooses quantities only.
Rounds are numbered 0 to 17, which is the 18 rounds above. Round 17 is a sell-down round: the students' phones tell retailers to clear the shelf.
Everything below is on the instructor console, scope2-control.html, reached from the Open the instructor console → button on the SCOPE 2 page.
In CREATE A GAME set Class size (students) to the number of bodies in the room (5–60; it builds chains of 6, stretching one to 7 or squeezing one to 5). Leave Seed blank unless you want two classes to face an identical demand series, and leave Demand persistence ρ at 0.6. Click ▶ Create the game.
A 4-letter Join code and a QR appear. Students open scope2.html, type the code and their name, or just scan. Watch the Seats filled tile climb until it matches the room.
In GAME SETUP - THE MARKET'S DESK the defaults are already sensible: Capped rounds 7,8,13 at Severity 0.6 (suppliers get only 60% of what they ordered). Click Apply cap schedule. You can also broadcast a warning - “Shortage may hit in Rounds 6–8” - which every student sees, while which rounds actually bite stays yours. Regenerate series only works in the lobby; once Round 0 starts the demand is frozen.
Tick Auto-run and set Seconds per phase (allowed 5–600, default 120, Manufacturer 180 - see the timing table below; 20–25 is the classroom number). Click ▶ Start round. From here every phase closes itself and you do not touch the console again: a missing bid is filled in at the price ceiling ($25.00 by default), missing orders and deliveries at 0.
Keep the console tab open and the laptop awake. The countdown is driven by this page polling the server every few seconds - close the tab and the clock stops. Force-advance phase always overrides, and Close bidding & allocate only lights up during the bidding phase.
Click ⛶ Presentation for a full-screen projector view (Esc to leave). When you are out of time, ■ End game stops it wherever it is and prints the FINAL SCOREBOARD - you do not have to reach Round 17. For the debrief, keep CHAIN LEADERBOARD and ALLOCATION - ONLY YOU SEE THIS TABLE on screen.
A round is six phases: bids → retailer orders → wholesaler → distributor → manufacturer → supplier. So the seconds-per-phase setting multiplies by six.
| Seconds / phase | One round | All 18 rounds |
|---|---|---|
| 15 - fast | 1.5 min | 27 min |
| 20 - brisk | 2 min | 36 min |
| 25 - recommended | 2.5 min | 45 min |
| 60 | 6 min | 108 min - too long |
A 90-minute class: 10 min set up and join · 5 min explain the six steps above · 45 min play at 25 s/phase · 5 min final scoreboard · 20 min debrief · 5 min spare. A 50-minute class: run at 15 s/phase and press ■ End game at Round 10 - the bullwhip has already happened by then.
Each student sees only their own seat. That blindness is the lesson, so resist the urge to explain what the others have.
Whose turn it is, plus six dots showing where the round has got to.
Your shelf stock, your P&L so far, and your economics per unit - what you pay landed, what you sell at.
Retailers get a bid box, then an order box. Everyone else gets deliver-down then order-up, with ±10 steppers.
Below that: their own chain (only their node carries numbers), their round-by-round worksheet, and their private order channels. They never see another seat's stock, cost or bid - only the instructor console does.
Put the CHAIN LEADERBOARD on the projector and ask these in order. The answers are already on the screen - you are only pointing at them.
The data shows the cheapest retailer usually sold the most units and made the least money. Sara's 780 cans at $1.50 look like a triumph until you put them beside a mid-priced shop selling 400 at $3.00. Volume is not profit.
The data shows the shortage cascade in the allocation table: demand that a cheap shop could not serve walked straight to the next-cheapest shop with stock. Someone in the room got a windfall they did not earn. Your stock-out is your rival's best round.
The data shows spikier - and worse the further upstream you sit. The supplier's order line will swing far harder than the market's demand line, even though the supplier never met a customer. That is the bullwhip, and you made it out of a one-round delivery delay.
The data shows the chains near the bottom are rarely the ones who sold least - they are the ones who ordered most and sat on it. Inventory is not an asset in this game; it is a standing charge.
Close on this. Ask who, if they played again, would bid nearer the middle. Almost every hand goes up - and that is the entire pricing lecture, delivered by them, in one sentence.
Four shops compete on price for one pool of demand while a five-tier chain behind them delivers a round late. Price sets share, stock sets whether you can serve it, and the delay creates the bullwhip without anyone intending it.
Each round: the Market announces demand → retailers seal a bid → the allocation splits demand by price, with a floor share for the dearest and a cascade when a shop runs dry → orders flow up one tier at a time → deliveries land next round and are paid on arrival.
Bid in the middle. Order what you can actually sell, not what you hope to sell, because every leftover can is charged holding every round and written off at the end.