> **DRAFT** — under teacher review. # Activity — Design a Hot Cross Bun Matrix The Hamilton and Alexandra College · Year 12 · 2026 The fastest way to learn how to *design* an evaluation matrix — and then decide **which elements of the winning design need to be developed further** — is to build one for something real and edible. CHOICE rates hot cross buns with the same discipline it rates headphones; in this activity, so will you. By the end you'll have designed, run, defended a matrix *and* produced a "further develop" list — the exact deliverable for **C4-2** and **Unit 4 Outcome 1**. [CHOICE's actual hot cross buns review-and-compare](https://www.choice.com.au/food-and-drink/bread-cereal-and-grains/bread/review-and-compare/hot-cross-buns) is the reference matrix you're learning from. {{Video|src=https://www.youtube.com/watch?v=k7m04xW0fzk}} **🎯 Watch first:** notice the panel scores against *agreed criteria*. Your job today is to decide those criteria — and defend them. --- ## The challenge We're comparing two real CHOICE-reviewed buns — **Woolworths Bakery Chocolate** vs **Coles Finest Luxurious Fruit**. Working as a review panel, you will: 1. Design an evaluation matrix. 2. Use it to crown a winner. 3. **Decide which elements of the winning bun design need to be developed further** — including elements your matrix did *not* score. That third step is the headline skill for [C4-2](/sd/C04/C4-2%20Checkpoint%20-%20Evaluation%20Matrix). It's the harder one — and the one most students skip. --- ## Step 1 — Read CHOICE's matrix We're not starting from scratch. CHOICE ran an actual review in March 2025 — a blind taste test of 19 supermarket and bakery buns. Two of their top picks are on the bench:  | Product | CHOICE Rating | Type | Toasted | Fresh | Buns/pack | Price/bun | |---|---|---|---|---|---|---| | **Woolworths Bakery Chocolate** (Cadbury chips) | 95 | Chocolate | 97% | 93% | 6 | $0.73 | | **Coles Finest Luxurious Fruit** | 85 | Traditional | 83% | 87% | 4 | $1.38 | *Source: [CHOICE Hot Cross Buns review and compare](https://www.choice.com.au/food-and-drink/bread-cereal-and-grains/bread/review-and-compare/hot-cross-buns), last updated 20 March 2025. Card layout, data and product photography reproduced from CHOICE for educational analysis.* --- ## Check Your Understanding What is the score of **95** calculated for *Woolworths Bakery Chocolate*? >| **The CHOICE Expert Rating is the average of the Toasted and Fresh scores.** >| >| Woolies: Toasted **97%**, Fresh **93%** → (97 + 93) ÷ 2 = **95**. >| Cross-check on Coles: Toasted **83%**, Fresh **87%** → (83 + 87) ÷ 2 = **85**. ✓ >| >| Three things this tells you about CHOICE's matrix: >| >| - **Toasted and Fresh are weighted 50/50** in the Expert Rating. >| - **Price per bun is *not* in the Expert Rating** — CHOICE shows it on the card but doesn't fold it into the headline score. >| - **Buns per pack is nowhere in the calculation** — which confirms why it isn't really a criterion. > [!IMPORTANT] > **The CHOICE cards show two things at once: a matrix and scores.** > > The **matrix** — which criteria exist, the weights, the formula behind the Expert Rating — is what CHOICE *designed* before tasting any buns. That's the equivalent of your **C4-2 checkpoint**: you build the matrix and defend it. > > The **scores** — 97%, 93%, 85, 95 — get filled in *afterwards*, when real products are run through the matrix. That's your **validation**: evaluating a finished solution against the matrix you designed. > > One artifact, two jobs — and *the matrix has to exist before the scores can mean anything*. --- ## Step 2 — What is your matrix built for? (your [SRS](/sd/C04/Evaluation%20Criteria%20and%20the%20SRS)) Before you taste anything, notice what's already obvious: these aren't the same product. One is chocolate, one is traditional fruit. One is $0.73 per bun, the other $1.38 — nearly double. CHOICE's Expert Rating crowns Woolies Chocolate (95) over Coles Fruit (85). But that ranking came out of *CHOICE's* matrix for *CHOICE's* view of "best hot cross bun" — and your persona is not CHOICE. Criteria come **first**, never invented afterwards to crown the bun you happened to like. Working from the [seven design decisions](/sd/C04/Designing%20an%20Evaluation%20Matrix), agree on: - **Who you're recommending for** — the persona drives everything. *"Best bun for a family's traditional Easter breakfast"* and *"best bun for the kids' lunchbox snack"* will not pick the same winner. - **Your criteria** — the handful that decide it for that person. Watch out: some criteria (like *"traditional fruit & spice flavour"*) really only apply to one of these two buns. Decide upfront whether you score that as 0–1 for the chocolate bun, or exclude it because your persona doesn't demand it. - **How each is measured** — blind panel rating for the eating qualities. The CHOICE data above is legitimate input for *value*, *price*, and a *sanity check* on toasted/fresh. - **Weights, justified** — where your point of view lives. - **A scale** (use 0–5). - **What you deliberately exclude, and why** — *flag these now; they come back in Step 5.* > [!TIP] > When you list **your criteria**, scan both halves of your [SRS](/sd/C04/Evaluation%20Criteria%20and%20the%20SRS): the **functional** requirements (*what* the system must do) and the **non-functional** requirements (*how well* — speed, usability, accessibility, security). Every requirement is a candidate matrix row; pick the handful that decide it for *your* persona. --- ## Step 3 — Taste blind, score independently (Validation) Two habits that are real evaluation skills, not just fairness: - **Blind it.** Label the brands A, B, C with the names hidden. If you can see the brand, the brand scores it for you. - **Score alone first, then compare.** If everyone just agrees with whoever speaks loudest, you've measured confidence, not buns. Apply your weights to each brand's scores to get a **weighted total**. --- ## Step 4 — Crown the winner (Validation) - **Explain** which bun proceeds, citing at least two criteria and their scores. - **Justify** by **naming the rival**: what does your winner give up compared with the runner-up, and why is that trade-off worth it for your persona? --- ## Step 5 — Decide what to develop further (Validation) You now know *which* bun wins. The harder question — **the C4-2 deliverable** — is: *which elements of that winning design need detailed design work next?* The matrix on its own doesn't answer that. Look in **two** places: **(a) Where your winner scored weakest.** If your winner beats the rivals overall but only got a 3 on *texture*, that is a development priority. The detailed-design task isn't "is the texture good enough?" — it's "*how* will we improve texture in the next version?" **(b) Requirements the matrix didn't score.** This is the bit students miss. The matrix scores criteria *the persona uses to choose between options* — taste, value, freshness. But your project has requirements that don't decide *one bun over another*, and so don't earn a matrix row, yet absolutely affect the final product. **Packaging** is the classic case: > The requirement *"attract more customers to consider buying it"* is real — but packaging doesn't change how the bun eats, so it stays out of the matrix. It still has to be designed properly. It belongs on your "develop further" list anyway. A quick test for any candidate element: > *"If two designs tied on this, would it show up in the matrix?"* If **no**, but it still has to be **designed properly**, it goes on your develop-further list. **Now produce three things to develop further** — at least one from **(a)**, at least one from **(b)**. > [!NOTE] > In C4-2 this is the headline output. The matrix names the winning *idea*; the deliverable is which **elements** of that idea become detailed designs. Packaging-not-in-matrix is your worked example of source (b). --- ## Your scoring sheet | Criterion (weight) | Method | Woolworths Bakery Chocolate | Coles Finest Luxurious Fruit | |---|---|---|---| | | | | | | | | | | | | | | | | **Weighted total / 5** | | | | **To develop further:** 1. *(from (a) — a matrix-scored criterion the winner is weakest on)* 2. *(from (b) — a requirement the matrix didn't score, e.g. packaging)* 3. *(your call — either source)* --- ## Why this matters The buns are a stand-in. The design decisions are **identical** when you evaluate your own software design ideas in [C4-2](/sd/C04/C4-2%20Checkpoint%20-%20Evaluation%20Matrix). The matrix tells you which idea proceeds; the develop-further list tells you what your detailed design has to *do*. Both come out of this one activity. --- ## See also - [Designing an Evaluation Matrix](/sd/C04/Designing%20an%20Evaluation%20Matrix) — the seven design decisions in full - [CHOICE Headphones — Spotting Efficiency and Effectiveness](/sd/C04/CHOICE%20Headphones%20-%20Spotting%20Efficiency%20and%20Effectiveness) — the same matrix discipline applied to a software-flavour example - [C4-2 Checkpoint — Your Evaluation Matrix](/sd/C04/C4-2%20Checkpoint%20-%20Evaluation%20Matrix) · [Efficiency vs Effectiveness](/sd/C04/Efficiency%20vs%20Effectiveness) - Reference: [CHOICE hot cross buns review-and-compare](https://www.choice.com.au/food-and-drink/bread-cereal-and-grains/bread/review-and-compare/hot-cross-buns) --- ← Back to [C04 Home](/sd/C04/C04-home) · [VCE Software Development Hub](/sd/VCE%20Software%20Development%20Hub)