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Worksheet Grade 7 Art & Music

Hagley's New Water Meter Lids: A Cast-Iron Pattern Worksheet

Grade 7 students plan a raised pattern for a fictional town's iron meter-box lids, working with scale, slip rules, symmetry, and how wear creates value.

Objectives

  1. Students will compute drawn and actual sizes for a lid design at a stated scale and rescale the design for a larger lid.
  2. Students will explain how raised texture, wear, and dirt create value and contrast on a cast-iron surface.
  3. Students will justify a radially symmetric layout for a round lid and argue for one finalist design while answering a counterclaim.

Vocabulary

Water meter
A device that measures how much water a home or business uses so the utility can bill fairly. Reading the meter can also reveal hidden leaks.
Service line
A service line is the small pipe that connects the water main under the street to the plumbing inside one home or building. It is the last leg of the trip water makes to your tap.

Also: relief, radial symmetry, value, contrast, slip resistance, scale factor

Teacher overview

The town of Hagley and its lid contest are fictional. In many towns, a service line runs from the water main under the street to a meter in a small box near the curb, and a round lid set level with the sidewalk covers that box. This worksheet asks students to plan the raised pattern cast into Hagley's new iron meter-box lids. Part A has them draw the entry to scale and resize it, Part B asks how wear, dirt, and symmetry shape the design, and Part C asks them to argue for one of two finalist designs.

Teaching note: students often assume the patterns on sidewalk lids and covers are purely decorative. The raised texture's first job is grip, since a smooth iron disk becomes slippery when wet, so the art has to work inside that rule. A second misconception concerns value. On bare cast iron there is no paint to make lights and darks, yet worn lids still show strong contrast, because shoes polish the raised parts until they shine while grit settles into the low spaces. Items 8 and 9 build on this, and it is worth showing students a photograph of a worn cover from the school's own sidewalk if one is available.

Hagley's New Water Meter Lids: A Cast-Iron Pattern Worksheet — Grade 7 Art & Music
Name: ____________________________ Date: ______________

Student Worksheet

In our scenario, the town of Hagley is replacing the old lids on its water meter boxes. A water meter box is a small box buried near the curb in front of a home. It holds the meter that measures how much water the home uses. The round iron lid sits level with the sidewalk, so people walk and bike over it every day.

The town is holding a student contest to design the raised pattern that will be cast into the new lids. Here are the contest rules.

  • Each lid is a circle 12 inches across.
  • The pattern is made of raised lines and shapes that stick up from the lid.
  • No smooth, flat area may be wider than 1 inch, so shoes and bike tires do not slip.
  • The word WATER must appear, with letters at least 1.5 inches tall.
  • A plain ring 3/4 inch wide runs around the edge of the lid.
  • Entries are drawn at a scale of 1 inch on paper to 2 inches on the lid.

Part A: Drawing to scale

  1. How wide is the lid on the entry drawing, in inches?
  2. What is the smallest height the letters of WATER can have on the drawing?
  3. How wide is the plain edge ring on the drawing?
  4. A student's drawing has a smooth circle in the center that measures 1.5 inches across on paper. How wide would that smooth circle be on the real lid?
  5. Does the smooth circle in item 4 follow the slip rule? Explain what the student should change.
  6. The town also needs larger lids, 18 inches across, for big meters. It wants the same design, scaled up. By what scale factor must the design grow?
  7. On the 18-inch lid, how tall will the smallest WATER letters be?

Part B: Pattern, value, and wear

  1. Over time, shoes polish the raised parts of an iron lid until they shine, while dirt settles into the low spaces. After a few years, which parts will look lighter?
  2. The town wants WATER to stay easy to read for many years. Should the letters be raised or sunk into the lid? Explain using value and contrast.
  3. A round lid can drop into its frame turned any way, and workers do not line it up when they put it back. Why does a pattern with radial symmetry suit a round lid better than a picture that only looks right one way up?
  4. The word WATER reads right side up from only one direction. Describe a layout for the word that works for people walking from either direction.

Part C: Choosing a design

Two finalists both follow every rule. Design A covers the lid in a tight grid of small raised water drops, with WATER in a band across the middle. Design B has raised wave lines that curl out from the center, with WATER curved in an arc just inside the edge ring.

  1. Write a paragraph to Hagley's public works department. Choose Design A or Design B. Give two reasons for your choice, and answer one argument that someone might make for the other design.

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

Answer Key
  1. Answer: 6 inches.
    At 1 inch on paper for every 2 inches on the lid, 12 / 2 = 6 inches.
  2. Answer: 0.75 inch.
    The real letters must be at least 1.5 inches tall, and 1.5 / 2 = 0.75 inch, which is 3/4 inch.
  3. Answer: 0.375 inch.
    The real ring is 3/4 inch wide, and 0.75 / 2 = 0.375 inch, which is 3/8 inch.
  4. Answer: 3 inches.
    Each inch on paper stands for 2 inches on the lid, so 1.5 x 2 = 3 inches.
  5. Answer: No, because the smooth circle would be 3 inches wide, and the limit is 1 inch.
    The student should fill the center with raised texture, such as small drops or ridges, or shrink the smooth area to no more than 1/2 inch across on the drawing.
  6. Answer: 1.5 times.
    The new lid is 18 inches across and the old one is 12 inches, and 18 / 12 = 1.5.
  7. Answer: 2.25 inches.
    Every length grows by the same factor, so the smallest letters grow from 1.5 inches to 1.5 x 1.5 = 2.25 inches.
  8. Answer: The raised parts.
    Polished iron reflects more light, so the raised lines and shapes look light and shiny. The low spaces fill with dirt and look dark.
  9. Answer: Raised.
    Raised letters are polished light, while the low areas around them turn dark, so the word keeps strong value contrast. Sunk letters would fill with dirt and grit, which blurs their edges and makes them harder to read.
  10. Answer: A radially symmetric pattern looks correct no matter how the lid is turned.
    Because the lid can end up in any position, a picture with a clear top and bottom will often sit sideways or upside down. A pattern that repeats evenly around the center always looks intended, and its shape echoes the circle of the lid.
  11. Answer: Accept any layout that reads from both directions, such as printing WATER twice, facing opposite ways.
    Other good answers: running the word around the lid in a circle so that part of it faces each direction, or placing it in two arcs on opposite sides of the center.
  12. Answer: Either design earns full credit when the paragraph states a clear claim, gives two reasons, and answers one opposing point.
    Reasons for Design A might include strong grip from the even texture, easy reading of the straight WATER band, and a calm pattern that wears evenly. Reasons for Design B might include radial symmetry that looks right from every direction, movement that suggests flowing water, and an arc of letters that follows the round shape of the lid. A strong counterclaim response names the other design's best feature and explains why the chosen design still serves the town better.

Differentiation

Support

Give students a printed 6-inch circle, already at the contest scale, with the 3/8-inch edge ring marked, so they can measure their answers to items 1 through 4 and see the smooth-circle problem in item 5 directly. For item 12, provide an argument frame: "Hagley should choose Design ... because ... and because .... Some people might prefer Design ... because ..., but ...".

Extension

Suppose the fictional town also wants a matching lid for its fire hydrant valve boxes, which are 8 inches across. Ask students to find the scale factor from the 12-inch lid (8 / 12, or 2/3), work out whether the smallest WATER letters would still meet the 1.5-inch rule, and redesign the lettering if they would not. Students who finish can draw a full entry for their chosen design on the printed circle, shading raised parts light and low spaces dark to show the lid after years of wear.

ELL supports

Show a labeled sketch of a meter box from the side (sidewalk, lid, box, meter, and the pipe to the house) before students read the scenario. Pair the words raised and sunk with a quick demonstration using a coin or a textured tile. Allow students to answer items 8 through 11 with a labeled sketch and a short phrase, and let them plan the item 12 paragraph orally with a partner first.

Extensions

Many cities have decorative iron covers on their streets and sidewalks, some designed through public art programs. Students can photograph three covers or lids near the school (from the sidewalk, never in the street), sketch each one, and sort them by how their texture handles grip, symmetry, and lettering, then note which one has kept its contrast best after years of wear.