Classroom activity Grade 4 Engineering & Design
Foxmarsh Pond Oil Spill: A Boom Material Fair Test
A grade 4 hands-on station activity in which teams fair-test three floating boom materials against hold, float, and setup rules before recommending one to a park.
Objectives
- Students will run a fair test that changes only the boom material.
- Students will record where each boom design failed during the two-minute hold.
- Students will recommend one boom material using the park's three rules and its token limit.
Vocabulary
Key words: boom, spill, fair test, failure point, float
Teacher overview
Teams of three run the same spill test three times, changing only the material the floating barrier is made from, and then recommend one material to the parks department of Foxmarsh, a town invented for this activity. The classroom setup follows the real job closely: a boom is a floating barrier that holds a spill in one place so it can be picked up, so the test asks what a crew asks, which is whether the barrier holds the oil, stays afloat, and can be set by one person quickly. Because every team runs all three materials on the same tray with the same amount of oil, the activity also gives a clean example of changing one variable at a time. Expect 55 minutes, including cleanup.
Activity Directions
Before class (15 minutes of prep). Cut each boom material to the same 20-inch length, enough to close into a ring about 6 inches across: a braid of cotton yarn, a strip of foam pipe insulation, and a sleeve of plastic mesh loosely stuffed with cotton balls. Set out one tray per team with about two inches of water. Stir a pinch of cocoa powder into the vegetable oil so students can see it against the water. Check for food allergies first, and do not use peanut oil. Put a trash bag at each table for oily paper towels.
Set the scene (5 minutes). Tell the class a delivery truck leaked cooking oil into the boat pond at Foxmarsh Park. The oil floats, so the parks crew wants a boom that traps it in one spot until a skimmer arrives. Read the three rules the parks department wrote: the boom must keep the oil inside its ring for 2 minutes, it must still be floating at the end, and one person must be able to set it in place in 30 seconds. Then read the limit: the park will spend no more than 10 supply tokens for enough boom to ring the spill.
Set the fair-test rules (5 minutes). Together, list what will stay the same for all three tests: the same tray, the same water, the same 1 tablespoon of oil, the same ring about 6 inches across, the same 2-minute timer, and the same calm spot away from a fan or an open window. Write the list where everyone can see it. Ask what would happen to the comparison if one team used twice as much oil, and let students answer before moving on.
Run Test A, the yarn braid (8 minutes). One student sets the yarn ring in place on the water while a teammate times it; record the seconds in the table. Then spoon the oil into the middle, start the timer, and watch. At 2 minutes they record whether oil escaped, where it escaped, and whether the boom still floated. Lift the boom out with a paper towel and wipe the tray, keeping the same water.
Run Test B, the foam strip, and Test C, the mesh sleeve (15 minutes). Repeat step 4 for each material, changing nothing but the material. Remind teams to use the same tablespoon of oil each time. A team that spills extra oil should start that test over rather than adjust the timer.
Score against the rules (5 minutes). Teams mark each material yes or no on all three rules, then note each material's token cost, which is printed in the handout table: yarn braid 3 tokens, foam strip 6 tokens, mesh sleeve 8 tokens.
Recommend and debrief (2 minutes). Each team names one material to the parks department and gives the rule that ruled out each of the other two. Close with two questions to the whole class: which rule, if any, did the cheapest material break, and what one change would you test next on the material you recommended?
Cleanup. Oily towels go in the trash bag, never down the sink, which is the same rule real utilities ask households to follow with cooking grease. An adult pours the tray water off through a paper towel in a strainer and throws the towel away.
Student Handout
The job
A delivery truck leaked cooking oil into the boat pond at Foxmarsh Park. Oil floats on water. A boom is a floating barrier. It holds the oil in one place so a crew can pick it up.
The park's rules
- The boom must keep the oil inside its ring for 2 minutes.
- The boom must still be floating at the end of the 2 minutes.
- One person must be able to set the boom in place in 30 seconds.
- The park may spend no more than 10 supply tokens.
What stays the same in every test
The same tray. The same water. The same 1 tablespoon of oil. The same ring, about 6 inches across. The same 2-minute timer. Only the boom material changes.
Record your tests
| Test | Material | Cost in tokens | Did oil escape? Where? | Still floating at 2 minutes? | Seconds to set it in place |
|---|---|---|---|---|---|
| A | yarn braid | 3 | |||
| B | foam strip | 6 | |||
| C | mesh sleeve | 8 |
Write your answers
- Which rule did each material break, if any? Write one line per material.
- Which material do you recommend to the parks department? Give the rule that ruled out each of the other two.
- Where did your recommended boom come closest to failing? Name the exact spot on the ring.
- Name one change you would test next on your recommended boom, and say what you would keep the same while you test it.
From Water for Schools (waterforschools.org). This material is in the public domain (CC0) and may be copied, edited, and shared freely.
Differentiation
Support
Pair these teams with a filled-in example row for Test A so the recording columns are clear before they run their own trial. Give them a printed strip listing the three rules in order, and ask them to check one rule at a time rather than judging a material all at once. A second adult or an older student at the table can manage the timer so students can watch the ring.
Extension
Ask these teams to test whether ring size changes the result, holding the material and the oil amount constant while making one ring 6 inches across and a second ring 10 inches across (cut a piece about 32 inches long for the larger ring). They should predict first, then explain any difference in terms of how far the oil has to travel before it meets the barrier, and note which of the park's rules a larger ring would make harder to meet.
ELL supports
Pre-teach spill, float, barrier, escape, and skimmer with sketches, and show a short mimed version of the whole test before anyone reads the handout. Let students record results with symbols and single words in the table, and provide the frames "The ____ boom let oil escape at the ____." and "I recommend the ____ boom because ____."
Extensions
Show the class photographs of real containment booms used on a river or harbor and ask which of the three classroom materials each real boom most resembles, then discuss the parts a classroom version leaves out, such as the weighted skirt that hangs below the surface and the anchor lines that hold the boom against a current. Ask what a crew would have to add to the classroom winner before it could work on a moving stream.