If you live in West Virginia, you already know what's piling up in the yard right now. The state's Department of Tourism reported in its Oct. 7 fall foliage update that color had swept across Tucker and Pendleton counties and was still spreading statewide. Beautiful on the hillsides. A lot of raking in the backyard.
Here's the good news: those leaves aren't trash. In his Oct. 2 Backyard Gardener column, J.J. Barrett of WVU Extension points out that mowing and mulching leaves returns nutrients to the soil, and that bagged leaves are great for the compost pile.
That makes this the perfect week to ask your kids a big science question: how does a pile of dead leaves turn into the soil that feeds next year's garden?
What your kids will learn
Grades K–5
- What soil is made of: tiny bits of rock, water, air and once-living things like leaves
- How decomposers (worms, fungi and bacteria) break leaves down
- What makes a test "fair": changing only one thing at a time
- Observing, drawing and comparing how seeds grow in different soils
Grades 6–12
- Soil composition, organic matter and the nutrient cycle
- How particle size and surface area affect the speed of decomposition
- Independent, dependent and controlled variables in a real experiment
- Measuring germination speed, plant height and root growth, then graphing results
This week's activity: The leaf decomposition race
You only need leaves from your own yard, some garden soil, three clear jars or zip-top bags, and a spray bottle.
- Gather leaves. Collect a big bag of dry fallen leaves. Wear gloves, and leave any mowing or shredding by machine to an adult.
- Make two sizes. Keep one pile of whole leaves. Crush the other pile by hand into small pieces.
- Set up three jars. Jar A: a scoop of garden soil plus whole leaves. Jar B: the same amount of soil plus crushed leaves. Jar C: soil plus crushed leaves, misted with water every few days so it stays damp. Label each one.
- Predict. Which jar will break down fastest? Have each child write down a hypothesis and a reason.
- Observe weekly. Keep all three jars in the same spot, loosely covered so air can get in. Each week, draw or photograph each jar and note color, smell and how much leaf shape you can still see.
- Talk about it. Smaller pieces give decomposers more surface to work on, and moisture helps them stay active. Older kids can rate decomposition on a 1–5 scale each week and graph it through the winter.
Wash hands after handling soil and leaves. This is a slow experiment on purpose: real leaf compost takes months, so it becomes a winter-long project your kids can check on.
Take it further: grow real plants in different soils
The leaf race shows how soil gets made. The next question is the one gardeners care about most: does what a plant grows in actually change how it grows? That's exactly what our Soil Science Experiment Kit (4 Pots) is built to test, right at the kitchen table while it's cold outside.
- In the box: four 3-inch peat pots, traditional potting mix, expandable coconut coir pellets, and 2 seed varieties chosen for fast germination
- The experiment: plant the same seeds in different growing media, and different seeds in the same medium, then track which sprouts first and grows best. Sprouting typically begins in 3–7 days.
- Curriculum and worksheets: 5 lessons for Grades K–5 or 6–12 (you choose at checkout), with an experiment planning sheet, a side-by-side growth tracking chart, and a reflection sheet or lab report template with graph. They're emailed after purchase.
Planning ahead for spring? Many gardeners use fall to set up a bed and let leaves start breaking down before planting season. Our Raised Garden Bed Plant Science Kit includes a 6 × 3 × 1 ft galvanized steel raised bed, 5 peat pots with seed-starting soil, 5 seed varieties, and a 5-lesson curriculum with worksheets. Filling the full bed takes about 18 cubic feet of additional garden soil, which is a ready-made volume math problem for older students.
Join the growing community
Every kit purchase includes an invitation to Aardvark's Seed Planting For Little Hands, our private group for families using our kits. Share your weekly leaf-jar photos, post which soil won your pot race, and compare notes with young growers across West Virginia, Arkansas, Arizona and beyond. While Arizona kids are planting their winter gardens, your crew can show everyone how the Mountain State makes its soil.
Ready to dig in?
Rake the leaves this weekend, start the jars, and turn the cold months into a real soil science unit.
- Soil Science Experiment Kit (4 Pots) – Compare Growing Media, with Curriculum & Worksheets: $39.90
- Raised Garden Bed Plant Science Kit (6 × 3 × 1 ft) – Outdoor Garden Lab with Curriculum & Worksheets: $113.97
Get the Soil Science Experiment Kit
Sources: West Virginia Department of Tourism, "Fall Color in Full Swing Across Almost Heaven" (Oct. 7, 2026); J.J. Barrett, WVU Extension, "Backyard Gardener: Fall lawn care guidance," Parkersburg News and Sentinel (Oct. 2, 2026).
