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Graphic organizer Grade 3 Engineering & Design

Limbrook Creek Mud Problem: A Grade 3 Design Frame

A grade 3 organizer that walks students from a muddy runoff chain behind a fictional school to written design goals, limits, and a choice between two fixes.

Objectives

  1. Students will trace a cause and effect chain from a bare bank to a muddy creek.
  2. Students will write three goals and three limits for a runoff fix.
  3. Students will score two fixes against the same goals and pick one.

Vocabulary

Key words: runoff, bank, goal, limit

Teacher overview

This organizer is a cause-and-effect chain feeding a criteria-and-constraints frame and a two-column scoring table, so the same page carries a student from noticing a problem to defending a design choice. The sequence follows the habit engineers rely on, which is writing down what a fix must do and what it may not cost before any fix is judged. Asked why a creek runs brown, third graders commonly look for someone who dumped something, since pollution is usually introduced to them as an act a person commits, and rain lifting soil off bare ground is easy to miss as a source in its own right. The chain in Part 1 exists to make that second source visible before students start designing.

Limbrook Creek Mud Problem: A Grade 3 Design Frame — Grade 3 Engineering & Design
Name: ____________________________ Date: ______________

Organizer

The town of Limbrook has a school beside Limbrook Creek. Read the scenario card. Then fill in every box in order.

Scenario card. Behind Limbrook School there is a bare dirt bank with no grass on it. When rain falls, brown water runs down the bank, crosses the gravel path, and pours into the creek. The creek turns brown for about a day. Fish lay eggs on the clean gravel at the bottom of the creek, and mud settling out of the brown water covers those eggs. The school has straw bales, wood chips, grass seed, and stones in the shed. One class has one afternoon to do the work. The gravel path must stay clear, because students walk on it every day.

Part 1. What happens now

Link Write what happens
Link 1: Rain falls on ...
→ Link 2: The water carries ...
→ Link 3: In the creek, the mud ...

Part 2. What must our fix do? (goals)

Goal Write it in your own words
Goal 1
Goal 2
Goal 3

Part 3. What limits us?

Limit Write it in your own words
Limit 1: materials
Limit 2: time
Limit 3: the path

Part 4. Score two ideas

Question Idea 1: spread wood chips over the bare bank Idea 2: lay a row of straw bales at the bottom of the bank
Does it meet Goal 1?
Does it meet Goal 2?
Does it meet Goal 3?
Does it stop mud from starting, or catch mud after it starts?
What could go wrong?

Part 5. Our pick

Box Your answer
We pick
One reason from Part 4
One change that would make our pick stronger

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

Completed Exemplar

Part 1. What happens now

Link Write what happens
Link 1: Rain falls on ... the bare dirt bank, where no grass holds the soil
→ Link 2: The water carries ... loose soil down the bank, across the path, and into the creek
→ Link 3: In the creek, the mud ... settles on the gravel and covers the fish eggs

Part 2. What must our fix do? (goals)

Goal Write it in your own words
Goal 1 Keep the soil on the bank so less mud reaches the creek
Goal 2 Stop the creek from turning brown after rain
Goal 3 Keep mud off the creek gravel where fish lay eggs

Part 3. What limits us?

Limit Write it in your own words
Limit 1: materials We may use only the straw bales, wood chips, grass seed, and stones in the shed
Limit 2: time We have one afternoon and one class
Limit 3: the path Nothing may be piled on the gravel path

Part 4. Score two ideas

Question Idea 1: spread wood chips over the bare bank Idea 2: lay a row of straw bales at the bottom of the bank
Does it meet Goal 1? Yes, the chips cover the soil so rain cannot lift it Only partly, because the soil still moves and the bales catch some of it
Does it meet Goal 2? Yes, much less soil leaves the bank, so much less brown water reaches the creek Partly, some muddy water still gets past or around the bales
Does it meet Goal 3? Yes, less mud reaches the creek to settle on the gravel Partly, some mud still gets past the bales and settles on the gravel
Does it stop mud from starting, or catch mud after it starts? Stops it from starting Catches it after it starts
What could go wrong? Heavy rain may wash chips off a steep spot Bales fill with mud and must be replaced, and a bale in the wrong spot blocks the path

Part 5. Our pick

Box Your answer
We pick Idea 1, with a short row of bales along the bottom edge away from the path
One reason from Part 4 Idea 1 stops mud from starting, and Part 4 shows that Idea 2 only catches mud after it has already left the bank
One change that would make our pick stronger Sow grass seed under the chips so roots hold the soil once the chips break down

Differentiation

Support

Fill in Link 1 of the chain and Goal 1 before handing the page out, so students begin with a model in front of them. Provide a picture strip of the bank, the path, and the creek gravel that students can point to while a partner writes.

Extension

Ask these students to add a third idea of their own using only the shed materials and to score it in the same table. Have them write which goal their idea protects best and which goal they traded away to get it.

ELL supports

Pre-teach bank, runoff, bale, and chips with photographs and a hand motion for water carrying soil downhill. Provide sentence frames such as "Idea 1 meets Goal ___ because ___." Allow the Part 4 cells to be answered with yes, no, or partly plus a small drawing.

Extensions

Walk the school grounds and look for a second bare spot where rain could carry soil toward a drain or a ditch. Students can fill a fresh copy of Part 1 for that spot and decide whether the pick they defended here would work there as well.