Project Grade 7 Art & Music
The Cressbrook Watershed Pocket Map: Line Weight by Stream Order
Grade 7 teams design a folding trail map of a fictional watershed, setting each stream's line weight by its stream order and making the divide stand out.
Objectives
- Students will assign a stream order to every stream segment and show that order through a consistent line-weight hierarchy.
- Students will enlarge a base map with a grid at a scale factor of 1.5 and redraw an accurate scale bar.
- Students will use a limited palette, contrast, and consistent icons so that a hiker can find the divide and the flow path quickly.
Vocabulary
- Watershed
- A watershed is all the land where rain that falls will drain to the same stream, river, or lake. Everyone lives in a watershed, no matter how far from the water they live.
- Tributary
- A tributary is a smaller stream or river that flows into a bigger one. Many small tributaries join together to build a large river.
Also: divide, stream order, line weight, visual hierarchy, legend, scale bar
Teacher overview
A watershed is all the land that drains to one point, and a good trail map can show a hiker, at a glance, that every stream underfoot is heading to the same place. In this project, grade 7 teams design a folding pocket map for the fictional Cressbrook Trail Association. The map must show the whole Cressbrook watershed, from the ridgeline divide down to the town of Upcott, where the creek leaves the watershed. The central design problem is visual hierarchy: teams rank every stream by stream order and give each order its own line weight, so the branching pattern reads from small headwater streams to the main creek. The deliverable is a folded 11-by-17-inch map with a legend, scale bar, icons, and a short back-panel explanation, tested by another team acting as hikers.
Teaching note: many students think a watershed is a body of water, such as a lake or a "shed" that stores water, rather than the whole area of land that drains to one outlet. Students also tend to rank streams by length, or to raise a stream's rank whenever any tributary joins it. The stream-order rule used here corrects this: a small stream joining a larger one does not change the larger one's order. On the art side, the most common first draft uses one pen for every stream, and the map reads as an even tangle of lines with no sense of which way the water goes.
Preparing the base map (about 20 minutes, once): on a 6-by-10-inch sheet, draw a closed, leaf-shaped ridgeline that nearly fills the page, with its narrow tip at the bottom where Cressbrook leaves the watershed at Upcott. Inside it, draw eight short first-order streams that begin just inside the ridgeline. Join them in pairs to make four second-order streams, join those in pairs to make two third-order streams, and join those to make the fourth-order main stem of Cressbrook near the bottom of the page. Add two more short first-order streams that flow straight into the main stem. Mark a trailhead, a footbridge, a waterfall on a second-order stream, a spring at the head of a first-order stream, a wetland, and the Upcott water intake near the outlet, and add a scale bar on which 2 inches equals 1 mile.
Project Brief
Driving question: How can a pocket map show hikers that every stream they cross drains to the same town, and which streams are the big ones?
Scenario: The Cressbrook Trail Association is a fictional group that cares for the trails in the Cressbrook watershed. It wants a new pocket map for hikers. The map should help people find their way. It should also show that all the water in these hills flows to Cressbrook and on to the town of Upcott, where the town takes its drinking water from the creek.
The stream order rule:
- A stream with no streams flowing into it is first order.
- When two streams of the same order join, the stream below them is one order higher.
- When two streams of different orders join, the stream below keeps the higher order.
Constraints:
- Start from the base map your teacher gives you. It is 6 by 10 inches, and 2 inches equals 1 mile.
- Enlarge it by a scale factor of 1.5 to fit an 11-by-17-inch sheet.
- Draw every stream in blue. Give each stream order its own line weight, from thinnest for first order to heaviest for fourth order. A simple plan is to make each order about twice as wide as the one before it.
- Draw the divide as a dashed line in a color that contrasts with everything else on the map.
- Use a palette of four colors plus black. In our scenario, the print shop charges for each color, so the association set this limit.
- Keep land colors light enough that the thinnest blue line still shows on top of them.
- Design six icons in one matching style: trailhead, footbridge, waterfall, spring, wetland, and water intake. Each icon must fit inside a half-inch square.
- Make capital letters in labels at least 1/8 inch tall.
- Include a legend, a scale bar, and a north arrow.
- On the back of the sheet, include a cover panel and a panel of 60 to 100 words titled "You Are in the Cressbrook Watershed."
Final deliverable: A finished map that folds to pocket size, plus your marked base map, your palette card, and your hiker-test notes.
Milestones
Session 1: Read the watershed (50 min). On a copy of the base map, trace the divide in pencil. Write the order of every stream segment next to it, using the stream order rule. Check the two short streams that flow straight into the main creek. Do they change its order? Output: a base map with the divide traced and every segment labeled 1, 2, 3, or 4.
Session 2: Enlarge with a grid (50 min). Draw a grid of 1-inch squares on the base map. It will be 6 squares wide and 10 squares tall. On your draft sheet, draw a grid of 1.5-inch squares, also 6 wide and 10 tall, so it covers 9 by 15 inches. Copy the ridgeline and the streams one square at a time. Redraw the scale bar for the new size, where 3 inches equals 1 mile. Output: an enlarged pencil draft with a correct scale bar.
Session 3: Design icons and choose a palette (50 min). Sketch each of the six icons three ways, then pick the set that matches best in line weight and shape. Choose your four colors. On a palette card, paint a patch of each land color and draw your thinnest blue line across it to test that it still shows. Output: an icon sheet and a tested palette card.
Session 4: Ink the final map (50 min). Transfer your draft to the final sheet. Ink the streams with the line weight for each order. Add the dashed divide, the light land colors, the icons, the labels, the legend, the scale bar, and the north arrow. Output: the finished map side of the sheet.
Session 5: Back panel, fold, and hiker test (50 min). Write your 60 to 100 word panel. Explain what a watershed is and why every stream on the map ends up at Upcott. Fold the map. Trade maps with another team. The testers get 30 seconds for each task: find the divide, trace the path of water from the waterfall to Upcott, and name the order of the main creek. Write one change you would make based on the test. Output: a folded map, hiker-test notes, and one revision note.
From Water for Schools (waterforschools.org). This material is in the public domain (CC0) and may be copied, edited, and shared freely.
Rubric
| Criterion | Emerging | Developing | Proficient | Advanced |
|---|---|---|---|---|
| Stream order and line weight | Most streams share one line weight, or many orders are labeled wrongly. | Orders are mostly correct, but the line weights do not follow them consistently. | Every segment has the correct order, and each order has its own consistent line weight. | Orders and weights are correct throughout, and the team explains why the two small streams do not change the main creek's order. |
| Visual hierarchy and palette | The divide and the streams are hard to find among other colors. | The streams show, but the divide or the thinnest lines get lost on some land colors. | The map uses four colors plus black, the divide contrasts clearly, and every blue line shows on its land color. | The hierarchy is clear from arm's length, and hiker testers find the divide and the flow path well within the time limit. |
| Scale and layout | The enlargement is distorted, or the scale bar is missing or wrong. | The enlargement is close, but the scale bar was not updated. | The enlargement matches the base map at a factor of 1.5, and the scale bar shows 3 inches equal to 1 mile. | Scale, legend, north arrow, and fold panels are all placed so that no fold cuts through a label or the scale bar. |
| Icons, labels, and back panel | Icons are inconsistent or unreadable, and the back panel is missing. | Icons share some features, and the back panel describes the area without explaining drainage. | Icons match in style and size, labels are legible, and the back panel explains what a watershed is and why all streams reach Upcott. | Icons read clearly at a half inch, and the back panel explains the divide and the flow to Upcott in words a first-time hiker would follow. |
Differentiation
Support
Give teams a draft sheet with the 1.5-inch grid and the enlarged ridgeline already drawn, so their time goes to copying the streams and to the line-weight and color decisions. Provide a checklist of every stream segment (ten first-order streams, four second-order, two third-order, and the main creek) with spaces to record each order, and a sheet of icon starters (simple outlines of a bridge, a waterfall, and a spring) that students can adapt into a matching set.
Extension
Ask teams to add the edge of a neighboring watershed across the divide, with two or three of its streams flowing the other way, and to design a symbol that shows a hiker standing on the ridge exactly where the water splits. Teams can also produce a large-print version for a trailhead kiosk, working out which line weights and label sizes must change when the map is enlarged again.
ELL supports
Provide a glossary card with a small sketch for watershed, divide, tributary, stream order, and line weight. Let students label stream orders with numbers before writing any words, and allow the back panel to combine a labeled diagram with shorter sentences. Pair students so that one reads the stream order rule aloud while the other applies it on the base map, then switch.
Extensions
Collect two or three printed trail maps or transit maps from local parks or the school library and have students critique how each one ranks its lines by weight and color. Students can then write a short note to the fictional Trail Association recommending one idea to borrow from the best example.