Designing a PFAS Public-Notice Sign for Harrow Valley

Hook (5 min): Project two versions of the same short message, one in a single flat block of gray text and one where the key sentence is large and bold with the details smaller beneath it. Ask students which they would actually read while walking past, and why. Take three or four responses without commenting on the "right" answer yet.

Direct instruction (12 min): Explain the situation students are designing for. Harrow Valley tested its Blackstone well field, found PFAS, and installed a treatment system that now removes them before the water reaches homes. PFAS are a family of long-lasting chemicals; the federal limit for two of them, PFOA and PFOS, is 4 parts per trillion each, under a rule finalized in 2024 that water systems must meet by April 2029. In May 2026 EPA proposed letting eligible systems apply for a two-year exemption, to April 2031, but the limits would not change and the proposal was not final as of September 2026. The district must post a notice that tells residents three things clearly: what was found, that the water is now treated, and where to get more information. Introduce three design tools that control what a reader sees first: visual hierarchy (the order your eye moves through a layout), contrast (differences in size, weight, and color that make something stand out), and legibility (type that is easy to read at a distance). Show how a headline, a short body line, and a small contact line create a top-to-bottom reading order.

Compare an older notice (8 min): Hand out a printed example of a plain older public-health notice (any simple historic sanitation or boil-water style bulletin the teacher selects). As a class, mark where the eye goes first and whether the most important message is easy to find. Discuss how a notice from a century ago and a modern sign are both tools a community uses to protect public health, and what has changed about how they are designed.

Guided practice (5 min): On scrap paper, students make two quick thumbnail sketches of a layout, deciding only what will be the biggest element, what will be second, and what will be smallest. No color or detail yet.

Independent design (15 min): Students draw their final Harrow Valley notice sign on 11-by-17 paper. It must include a clear headline, one plain sentence saying the water is now treated, and a small line pointing readers to more information. They apply hierarchy and contrast so the headline reads first. On the back, each student writes one sentence naming which element they made largest and why.

Closure and formative check (5 min): Hold a silent gallery walk. Each student places a small mark on the one classmate sign whose main message they understood fastest. As an exit ticket, students answer on an index card: "Name one design choice that made a sign easy to read from across the room." Collect and scan; if fewer than three-quarters of cards name a specific choice such as size, bold weight, or contrast, reteach hierarchy briefly next session.