Environmental Engineering Landfill Solutions

Learn about the environmental impact solid waste has on our earth and water. Kids get a chance to build their own landfills in this engineering challenge!

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Project Ingredients
Project Setup
Tips and Tricks

Creating safer landfills.

With National Engineering month (in March) and Earth month (in April) it seems fitting to combine the two into an environmental engineering unit. We’ve got four fun, Earth focused, engineering projects that come in a ready to go booklet form. Kids love going to the “store” to purchase their landfill liners or new hunks of clay for their projects. The aspect of a store helps kids understand the difference between Making (like the movement) and engineering. When we are Making, we get to use anything we want. Our imaginations are the limit. Want to use 500 popsicle sticks? Go for it. Need hot glue to hold everything together? Plug it in and get going!

Bringing engineering from endless building to thoughtful creating.

But engineers have to blend the world of Making with the real world, a world where supplies cost money (and are not infinite), and where some methods to connect items together isn’t safe, or even feasible. 

These lab books, one for each of our environmental engineering challenges, are a great way to gently make that transition. Kids keep track of their purchases on a store receipt and have the chance to return goods in their original condition for refunds. They also have a place to keep track of their scores, brainstorming, and even new vocabulary – all in one little booklet!

Ready to learn about our landfills, and then design your own? Let’s get started!

Cover page for the downloadable curriculum for the environmental engineering landfill challenge. Cover shows a student building a landfill and three images of pages included in the landfill claaenge lab book. One image shows the introduction page to the landfill design challenge, one image shows a landfill vocabulary page, one image shows the layers typically used to create safe landfills.

Project Ingredients

Ingredients For Landfill – Leo’s Store

Setting up your Landfill Solutions Environmental Engineering Challenge

Image collage of three images and the title Landfill Engineering Challenge, Kids Science Activity, Approved by Dr. Erica. Images show a student using clay to begin making a landfill, a clay landfill that looks similar to a cup, and a student filling their clay landfill in a sink with dyed cotton balls. This is used to test if the landfill is leakproof
  1. Print out enough booklets so each child participating has one.
  2. Set up your Landfill Leo store with the items on the list. If you need to, modify the list with materials you have on hand.
  3. Prep a space for the testing. This is best done in a sink. I like to keep the cotton balls, water jar, and food dye right there.
  4. Read over the lesson plan and key (included in the download)
  5. Prep videos to watch if you want to include any. I like “How a Landfill Works” and “Reading Rainbows Recycling Center“, but there are a ton of cool videos out there to show. I like to show the videos on a tablet that is in my line up area – this helps some students wait patiently for their turn to test.

Tips and tricks for the landfill engineering project

1. Use the booklet!

An image from the inside of the environmental engineering lab book that looks at building safer landfills. This page shows the store menu of supplies students can buy, like clay, popsicle sticks, and toothpicks, as well as a student tracking their purcahsed on a receipt

Seriously! The booklet has so much information in it for kids to use as a jump-off point. It also includes a vocabulary list with corallary images that they can match the new words up to. Another benefit is that students will be recording their work – which is an important skill to learn. So print out the booklet and use it! It will make your life easier and this one is FREE – so there is really no barrier.

2. Plug into the gross factor.

Two students put their clay landfill in a sink for testing. They begin by filling the engineered landfill with dye soaked cotton balls. The more cotton balls they can fit in their landfill, the higher their point score is.

Kids are definitely aware that it is better for the Earth to recycle versus put things in a landfill. But they aren’t necessarily aware that landfills have an environmental impact past the idea of not reusing an item. In my classes I ask kids to imagine my kitchen trash bag. It’s got packaging from raw chicken I ate last night, dirty diapers from my baby neice, maybe even some CR2032 batteries that accidently got thrown in during a rushed clean up. I ask them to imagine me pulling this bag out of the trash and adding in a bunch of water. The bag holds the water great, so there is no mess on the floor, and I decide to let it just stew there for a week or two.

Then I ask my kids to imagine poking holes in the bottom of the trash bag and taking a shower in it. Would they want to do that? Would they want to get a cup of water from the faucet if the bag was sitting in the sink with all that gross water around? This is how I help kids understand what leachate is, and why we would want to make sure it gets treated properly. You could even talk about watering your garden tomatees with that water – how do they feel about that idea? 

And this really happens in landfills. The liners that we use are not perfect – over time, stress, summer heat and winter cold, they begin to spout small holes that turn into larger holes. Those holes would then let the leachate, that super gross water, into the ground so it can go to a stream – ick! This opens up a conversation about why we want to collect the leachate. After thinking about this, I have even had some students install straw piping at the bottom of their landfills. These pipes allowed the rainwater to be collected and diverted to a new area!

3. Stick to the store

A student uses their hands to shape clay into a landfill structure. Students are building their clay on a piece of base cardboard meant to represent the earth.

It might feel easy to just let kids go at it with the supplies, but the overall budget constraint really helps this project gain a new dimension. By the end of my classes kids were returning supplies they found they didn’t need in order to purchase other supplies they found more useful!

4. Allow students to build their own idea

two students work on their landfill solutions environmental engineering challenge. Both students are building their landfills on top of a cardboard base and sculpting clay into cupl ike shapes.

This project has a scoring system, and often kids will want to do anything to try and win. There are bonus points for having your system control the leachate and be earthquake proof, however, some students might decide it is better to build an open cage type landfill that holds the most trash and takes the hit on thinking about our environment. While you may want to tell the student this isn’t allows, based on the rules it actually is.

What you can do, however, is use it as a way to open up the conversation to why many companies are big polluters – that is, that often the bonus (or fine) for being environmentally friendly isn’t large enough for companies to necessarily think of the environment first. They are often thinking of profit first. Instead of stifling these environmentally unsound landfills, use it as a stepping block for conversation. What would the point fine need to be to make them want to build a better landfill that thought about the environment?

What to expect for scores

I had a wide range of scores for this project, although the best scores came from kids who used their entire budget to purchase clay, and then sculpted a very large bowl to hold a lot of trash. This makes sense in that using double your money might get you tripple returns on the volume. I had a lot of younger hands in the 2-4,000 point range, while my 3rd and 4th graders regularly got into the 6-10,000 point range. My top scorer built a landfill using only clay and one straw, which they used to create a pipe for the leachate. They scored 13,500 points, mostly becuase their landfill held 125 cotton balls, for 12,500 points, plus the bonuses for being earthquake and water proof.