Lesson plan Grade 12 Art & Music

Designing an Accessible Water Quality Report: A Grade 12 Lesson

A grade 12 lesson where students translate real water-quality thresholds into an accessible infographic for a fictional utility, applying design and precision choices.

Grade: Grade 12
Subject: Art & Music
Material: Lesson plan
Time: 90 min
Prep: Low prep
Materials: Printed Anchor Bay data set and reference sheet (table in the procedure), Rulers or straightedges, Colored pencils or markers, or design software if available, Grid or graph paper for sketching layout

Standards

HSN-Q.A.3 Common Core Math

Choose a level of accuracy appropriate to limitations on measurement when reporting quantities.

How this material aligns: The exit ticket asks students to justify the number of decimal places they chose for one measurement on their infographic, directly applying this standard's reporting-accuracy judgment.

All materials for HSN-Q.A.3 →

HSN-Q.A.1 Common Core Math

Use units as a way to understand problems and to guide the solution of multi-step problems; choose and interpret units consistently in formulas; choose and interpret the scale and the origin in graphs and data displays.

How this material aligns: The direct-instruction worked example carries a lead reading and the regulatory action level through a consistent-unit percentage calculation, the multi-step, unit-guided reasoning this standard requires.

All materials for HSN-Q.A.1 →

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This material is in the public domain (CC0) and may be copied, edited, and shared freely, without attribution. Updated 2026-07-15.

Objectives

Students will translate real regulatory water-quality thresholds into an accessible one-page infographic.
Students will apply typographic hierarchy and color coding to communicate how close a reading sits to a safety threshold.
Students will choose an appropriate level of numeric precision when displaying water-quality data for a general audience.

Vocabulary

Turbidity: Turbidity is a measure of how cloudy or murky water looks because of tiny particles floating in it. Clear water has low turbidity, and muddy water has high turbidity.
Chlorine residual: Chlorine residual is the small amount of chlorine still left in the water after it leaves the treatment plant. It keeps protecting the water from germs all the way to your faucet.
Action level: A trigger number in lead and copper testing. If too many homes test above this level, the utility must take steps like improving treatment and telling the public.
pH: pH is a number that tells whether water is acidic, like lemon juice, or basic, like baking soda mixed in water. Pure water sits in the middle of the scale at a pH of 7.

Teacher overview

Every water utility publishes an annual water-quality report full of regulatory numbers that most residents never read, in part because the dense tables those reports rely on are not designed for a general audience. This lesson asks students to redesign that experience, translating four real regulatory thresholds into a one-page infographic for the fictional Anchor Bay Water Utility. A common misconception this lesson addresses directly is that adding more decimal places or more data always makes a report more trustworthy; in accessible design, the opposite is often true, since unnecessary precision and clutter make a reader less likely to notice the number that actually matters.

Procedure

Hook (10 min): Show students two contrasting mock report excerpts you create for this lesson: a dense table of numbers with no visual hierarchy, and a simple one-page graphic layout showing the same information. Ask students which one they would actually read if it arrived in their mailbox, and why.

Direct instruction (20 min): Introduce four design principles for communicating regulatory data: typographic hierarchy (making the most important number the most visually prominent), color coding a safety margin (such as a green-to-red band showing how close a reading sits to its limit), choosing an appropriate chart type for the kind of comparison being made, and matching numeric precision to what a reader actually needs. Model one worked example: the fictional Anchor Bay Water Utility reports a 90th-percentile lead sample of 3 ppb, against the real current lead action level of 15 ppb, which drops to 10 ppb in 2027 under the Lead and Copper Rule Improvements. Calculate what percentage of the action level that reading represents: 3 ÷ 15 = 0.20, or 20 percent, a useful number for a "how close are we" graphic element.

Anchor Bay data set and reference sheet: The readings are fictional. The limits are real federal standards. Print this table for students.

Measurement	Anchor Bay reading (fictional)	Real standard
Turbidity (finished water)	0.11 NTU	0.3 NTU limit
Chlorine residual (distribution average)	0.8 mg/L	4.0 mg/L maximum residual disinfectant level
pH	7.6	6.5 to 8.5 secondary (aesthetic) range
Lead (90th percentile)	3 ppb	15 ppb action level (10 ppb from 2027)

Guided practice (30 min): In pairs, students calculate two more percentage-of-limit figures using the Anchor Bay data set above, then sketch one chart or graphic element translating one of the four measurements into a visual with color-safety coding and an appropriately rounded label.

Anchor Bay's fictional finished-water turbidity reading is 0.11 NTU. Calculate what percentage of the real 0.3 NTU regulatory limit this reading represents.
Anchor Bay's fictional average distribution chlorine residual is 0.8 mg/L. Calculate what percentage of the real 4.0 mg/L maximum residual disinfectant level this reading represents.

Independent practice (20 min): Each student completes a full one-page mock infographic for the fictional Anchor Bay Water Utility, incorporating all four measurements (turbidity, chlorine residual, pH, and lead), each paired with a one-sentence, plain-language caption explaining what the number means for a resident, written at a more accessible reading level than the technical source data.

Closure / exit ticket (10 min): Students submit their infographic draft and answer one question on an index card: choose one measurement on your infographic and explain, in one sentence, why you chose the level of precision, meaning the number of decimal places, that you used.

From Water for Schools (waterforschools.org). This material is in the public domain (CC0) and may be copied, edited, and shared freely.

Answer Key

Answer: 36.7%.
0.11 ÷ 0.3 = 0.3667, or about 36.7 percent of the real 0.3 NTU turbidity limit.
Answer: 20%.
0.8 ÷ 4.0 = 0.20, or 20 percent of the real 4.0 mg/L maximum residual disinfectant level.
Answer: Answers vary (exit ticket).
Accept any response that ties the chosen number of decimal places to how the reading will be used, such as rounding turbidity to two decimal places because the regulatory limit itself is stated to one decimal place (0.3 NTU) and extra precision would not change what a resident needs to know.

Differentiation

Support (below grade level)

Provide the two guided-practice percentage calculations already set up as a fraction (reading ÷ limit = ___) so students complete only the division and rounding, and provide a partially designed infographic template with the four measurement boxes already outlined.

Extension (above grade level)

Ask students to design a second version of their infographic for a different audience, such as a version aimed at a city council rather than a household resident, and to explain in writing what design choices they changed and why.

ELL supports

Pre-teach "turbidity," "chlorine residual," "action level," and "pH" with simple definitions and an icon for each (a water drop, a chemistry flask, a warning triangle, a pH scale). Allow the plain-language captions in independent practice to be written as short phrases rather than full sentences.