Four Domains — the Science visual system

The design system for every Science artifact, Grades 3–10.

Mathematics has "Ten Times", in which each place is worth ten of the place to its right and the design says so before the words do. Grade 1 needed a second system, "Whole and Parts", because "Ten Times" is place-value specific and a Grade 1 class is not doing place value yet.

The lesson recorded at the end of NEW-LEARNING-AREA.md was blunt about what that means for a new learning area: expect to design a visual metaphor per area, not to inherit one. This is that design for Science.

1. The organising principle: the curriculum's own structure

The MATATAG Science guide does something no other curriculum guide in this repository does. On page 28 it prints a table called SEQUENCE OF DOMAIN PER QUARTER, and that table says each quarter is a domain. Elsewhere the guide's own phrase for the unit of work is "domain quarters".

So the year has exactly four blocks and each block has exactly one subject matter. That is not a convenience this repository imposed; it is the shape of the curriculum. Four hues, one per domain, is therefore not decoration — it is the table, drawn.

One domain keeps its name across all eight grades — Force, Motion, and Energy. The other three are renamed at the Grade 6/7 boundary. The hue does not change with the name, because the domain does not change with the name; a learner meeting amber in Grade 3 and amber in Grade 10 is meeting the same strand of the curriculum, which is exactly what a spiral progression is for.

Why this earns its keep at Grade 7

Grades 3–6 run the four domains in one fixed order. Grades 7–10 are a 4 × 4 Latin square — read any quarter across those four grades and each domain appears exactly once. Grade 7 opens on Science of Materials, Grade 8 on Life Science, Grade 9 on Force, Motion, and Energy, Grade 10 on Earth and Space Science.

Under this system that rotation is visible at a glance. Four wall charts side by side in a junior-high staff room open violet, green, amber, teal — a diagonal, not a column. A teacher who has internalised "Quarter 1 is violet" from the elementary grades sees immediately that Grade 8 is not, which is the misconception the guide's own table exists to prevent and the one that put three wrong rows into an early draft of this repository's Science research.

2. The second axis: three strands, always in the guide's order

The guide names three interrelated content strands (page 19) and says they are integrated throughout rather than taught separately:

1. Performing scientific inquiry skills
2. Understanding and applying scientific knowledge
3. Developing and demonstrating scientific attitudes and values

Every Science artifact carries these as a three-band spine in the header — always all three, always in that order, with the band for the strand this lesson leads with drawn solid and the other two drawn as outlines. Not as a claim that the lesson does only one of them, but so a teacher can see at a glance which one the assessment is pointed at.

The bands are neutral grey, never the domain hue. Two colour systems on one page competing for the same meaning is worse than one, and the domain hue is the one that has to survive a photocopy.

3. The three rules, applied

The three rules from ARTIFACT-SPEC.md §4 carry over unchanged. What they mean here:

1. One colour system, used identically everywhere. Violet means Materials on a Grade 3 slide, on a Grade 7 worksheet, on a Grade 9 wall chart and in the Grade 10 game. There is no artifact in which a hue means anything else, and no grade in which the mapping is re-chosen.

2. Show quantity truthfully. Science's version of drawing to scale is drawing evidence to scale. Where a diagram shows particle spacing, the spacing is drawn in proportion to the state it represents — a gas is not "a solid with wider gaps and the same picture". Where a Punnett square shows a 3:1 ratio, three cells are shaded and one is not, rather than a pie chart labelled 75%. Where a plate boundary diagram shows subduction, the descending slab is drawn at the angle the data gives.

3. Colour never carries meaning alone. Every domain-coded element is also glyphed, labelled, and hatched. The glyph is the fast channel on a photocopy; the label is the slow, certain one. A learner who cannot distinguish violet from teal reads ◆ and ■, and if the photocopy has eaten both, reads the words.

Contrast is checked rather than assumed. Each hue clears 4.5:1 on white and on its own tint, and no two of the four sit within confusable distance of each other in hue or in lightness. Semantic red #b3261e is reserved for "not yet" feedback and never used as a domain or content colour — which matters more in Science than in Mathematics, because "not yet" here is usually a misconception being named rather than an arithmetic slip being marked.

4. What the domain hue is applied to, and what it is not

Applied to: the header rule and grade badge on every artifact; the quarter blocks in the syllabus content map; the round headers in the game; the task numbers on the worksheet; the panel borders on the wall chart; the accent on the grade index card in the portal.

Not applied to: anything a learner is asked to classify. If a Grade 5 game asks is this a solid, a liquid or a gas?, the three options are not pre-tinted with an answer. The single most effective way to make a classification game unwinnable-by-thinking and trivially winnable-by-colour is to colour-code the categories being classified, and the domain hue is already spent on the page furniture.

Category colour, where a game genuinely needs it — the three states of matter, the three process skills, the three plate boundary types — is drawn from a neutral secondary set of slate, sand and plum, and is always introduced after the learner has answered, never before.

5. Typography and the classroom floor

Unchanged from the Mathematics system, restated because a new area is where these quietly slip:

• Body text on slides at 24 px minimum, readable from the back row
• Worksheets at 13.5 px, which is what fits an A4 page with real writing space
• font-variant-numeric: tabular-nums wherever measurements are compared in a column
• 44 px touch targets in every game, because the tablets are shared and the fingers are small
• prefers-reduced-motion respected; no animation carries information
• Every diagram that could be a photograph is a diagram, because photographs do not photocopy

6. One thing Science needs that Mathematics did not

A place to write down what was observed, separate from what was concluded.

The Key Stage 1 standard names observing, communicating, comparing, classifying, measuring, inferring, and predicting as distinct skills, and the commonest thing a learner does wrong across all eight grades is state an inference as an observation. Every learner-facing Science artifact that records anything therefore has two boxes, not one: what I saw, and what I think it means. They are the same size, so neither reads as the important one.

This is a design decision with a curriculum reason and it is the only structural element in the Science set that has no Mathematics counterpart.