Worksheet Grade 4 Science
Tracing Rain to Two Creeks on the Cobden Rise Map
A grade 4 worksheet on a fictional town's elevation map: students trace where rain runs, find the ridge that splits two creeks, and read each creek's direction.
Objectives
- Students will use heights printed on a town map to find the high ground and the two creek valleys.
- Students will decide which creek the rain at a given map square runs into and support the choice with numbers.
- Students will read a creek's flow direction from the heights printed along it rather than from the top or bottom of the page.
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.
Also: elevation, ridge, divide, downhill
Teacher overview
The town of Cobden Rise is fictional, and its map has Nethercomb Ridge running down the middle with a creek in the low ground on each side. Students read the heights printed at thirteen places on the map, trace which way rain runs from each one, and decide which creek the water reaches, so the map itself supplies every piece of evidence the items ask for. The misconception this worksheet is built to catch is reading down on the page as downhill. A student who assumes that every creek flows toward the bottom edge of a map, or that creeks always run from north to south, will get Quarnley Creek backward, because the heights along Quarnley Creek fall toward the north edge instead. Items 9, 10, and 11 are placed to surface that error while the map is still in front of the class.
Student Worksheet
The town of Cobden Rise has a long hill called Nethercomb Ridge. It runs down the middle of town. A creek runs in the low ground on each side of it. The map below is drawn in squares. The columns are A to F, from west to east. The rows are 1 to 5, from north to south. North is at the top.
| Row | A | B | C | D | E | F |
|---|---|---|---|---|---|---|
| 1 | woods | Thackley Brook | woods | ridge | woods | Quarnley Creek |
| 2 | farm | Thackley Brook | Ardsey Park (P) | ridge | library (L) | Quarnley Creek |
| 3 | farm | Thackley Brook | school (S) | ridge top (R) | bus garage (G) | Quarnley Creek |
| 4 | houses | Thackley Brook | ball field (T) | ridge | market (M) | Quarnley Creek |
| 5 | houses | water intake (W) | houses | ridge | houses | Quarnley Creek |
Thackley Brook leaves the map at the south edge, under square B5. Quarnley Creek leaves the map at the north edge, over square F1. Here are the heights printed on the map.
| Marker | Square | Height above sea level |
|---|---|---|
| R, top of Nethercomb Ridge | D3 | 452 feet |
| P, Ardsey Park | C2 | 396 feet |
| S, school | C3 | 372 feet |
| T, ball field | C4 | 340 feet |
| L, library | E2 | 388 feet |
| G, bus garage | E3 | 380 feet |
| M, market | E4 | 356 feet |
| Thackley Brook | B1 | 332 feet |
| Thackley Brook | B3 | 316 feet |
| W, water intake on Thackley Brook | B5 | 296 feet |
| Quarnley Creek | F1 | 300 feet |
| Quarnley Creek | F3 | 324 feet |
| Quarnley Creek | F5 | 348 feet |
In row 3, the ridge top R at D3 is 452 feet. Thackley Brook at B3 is 316 feet. Quarnley Creek at F3 is 324 feet. Which of these three places is the highest ground?
The school S at C3 is 372 feet. Thackley Brook at B3 is 316 feet. The ridge top R at D3 is 452 feet. Rain falls on the school roof. Does it run west to the brook or east to the ridge? Use two of the numbers to show how you know.
The bus garage G at E3 is 380 feet. Quarnley Creek at F3 is 324 feet. The ridge top R at D3 is 452 feet. Which creek does rain at the bus garage reach?
Rain in column C reaches Thackley Brook. Rain in column E reaches Quarnley Creek. Which column of squares is the line between them, and what is the name of the high ground that follows it?
In column C, Ardsey Park P at C2 is 396 feet, the school S at C3 is 372 feet, and the ball field T at C4 is 340 feet. Do these three heights rise or fall as you move from row 2 to row 4?
The ridge top R at D3 is 452 feet. The water intake W at B5 is 296 feet. How many feet lower is the intake than the ridge top?
Every height in the table is above 296 feet except the water intake W at B5, which is 296 feet. Tell why B5 is a good square for taking water out of Thackley Brook. Use the word downhill.
A truck spills a load of dirt at the market M, square E4, 356 feet. Quarnley Creek at F3 is 324 feet, and the ridge top R at D3 is 452 feet. Which creek will rain wash the dirt into?
Thackley Brook is 332 feet at B1, 316 feet at B3, and 296 feet at B5. Does the brook flow toward row 1 or toward row 5? How do you know?
Quarnley Creek is 300 feet at F1, 324 feet at F3, and 348 feet at F5. Does this creek flow toward row 1 or toward row 5? How do you know?
Write two sentences about the pattern on this map. In the first one, tell where the high ground is. In the second one, tell where the two creeks are and which way the land slopes.
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: The ridge top R at D3, 452 feet.
In row 3, 452 is greater than 324 and 316, so the middle of row 3 is the high ground and both creeks sit lower than the ridge.Answer: West, to Thackley Brook.
Water runs downhill. The brook at B3 is 316 feet, which is lower than the school at 372 feet, so water can reach it. The ridge at 452 feet is higher than the school, and water does not run uphill. Accept any answer that names one lower number and one higher number.Answer: Quarnley Creek.
The garage at 380 feet is lower than the ridge top at 452 feet and higher than the creek at 324 feet, so rain runs east and down into Quarnley Creek.Answer: Column D, which follows Nethercomb Ridge.
Column D holds the highest ground on the map, so it is the divide. Rain that falls west of it goes to one creek and rain that falls east of it goes to the other.Answer: They fall.
The heights go 396, then 372, then 340, so each row to the south is lower than the one before it. Accept "they get smaller" or "the land slopes down toward row 5."Answer: 156 feet.
452 - 296 = 156 feet.Answer: B5 is the lowest point on Thackley Brook, so water from the land west of the ridge runs downhill to it.
Every other marked place is higher than 296 feet. Rain that falls west of Nethercomb Ridge runs downhill into Thackley Brook, and the brook carries it south to B5, so the intake collects water from the whole west side of the map. Rain east of the ridge goes to Quarnley Creek instead.Answer: Quarnley Creek.
The market at 356 feet sits east of the ridge, and the creek at 324 feet is lower, so rain carries the dirt east and down. The ridge at 452 feet blocks it from reaching Thackley Brook.Answer: Toward row 5.
The heights go 332, then 316, then 296, so they get smaller toward the south, and water flows from the higher number to the lower one.Answer: Toward row 1.
The heights go 300 at F1, 324 at F3, and 348 at F5, so the creek is lowest at the north edge and flows that way. Watch for the answer "row 5," which comes from reading the bottom of the page as downhill instead of reading the numbers.Answer: The high ground runs down the middle of the map in column D, and the two creeks run in the low ground in columns B and F. A full-credit answer says the land slopes down from the ridge to the west toward Thackley Brook and down to the east toward Quarnley Creek. Accept any wording that names column D as the high line and the two outer columns as the low ground.
Differentiation
Support
Give these students a copy of the Cobden Rise map with the three heights in row 3 circled and an arrow already drawn from the school to the brook, then work item 2 aloud together before they start. For items 9 and 10, let students write the three heights in a column, largest at the top, and mark which end is the low end. A number line marked from 280 to 460 in twenty-foot steps helps students place the heights before they compare them.
Extension
Ask students to pick any two squares on the fictional map and write a new item like item 2, with an answer key that names the two heights that settle it. A second task is to mark where they would put a new bus garage so that its runoff reaches Quarnley Creek rather than Thackley Brook, and to give the heights that support the choice.
ELL supports
Pre-teach ridge, divide, downhill, and creek with a simple side-view sketch of the town of Cobden Rise showing the ridge in the middle and a creek on each side. Label the sketch with the words high, low, west, and east. Provide sentence frames for items 2, 3, and 8: "Rain at ___ runs to ___ because ___ feet is lower than ___ feet." For item 11, provide the frame "The high ground is ___. The creeks are ___."
Extensions
Have students find their own school on a printed topographic map or a state map that shows elevation, mark the nearest stream, and write which way rain leaves the schoolyard. Students can also imagine that a heavy storm drops rain on every square of the Cobden Rise map at once, then list the squares whose water arrives at the intake at B5 and the squares whose water leaves the map at the north edge instead.