Teacher's Guide: SOIL

Going Underground - In praise of dirt!

In the first of our Teachers Guide series we’re going to look at SOIL, why it is important and how we can care for it.  We give you simple step by step instructions on how to make a worm composter with your class.  

This is great for teaching children about the cycle of life, nature’s recyclers and also the importance of recycling their own food waste.  If you’re thinking about starting or improving a school garden or working on your Eco Schools - School Grounds action plan......this is for you! 


1. What is Soil?

Some call it dirt, but that’s a bit of a put down for a material teaming with life that is the lifeblood for plants and subsequently for us. Soil is SO much more than dirt - take a look at the microscopic world of soil and you’ll be fascinated.

Rocks, sand, silt and clay form the ‘skeleton’ of soils whilst the millions of living creatures and plants create the ‘flesh’ - a constant cycle of organic materials and nutrients.

Fascinating Fact: Did you know that 1 cup of soil can hold as many bacteria as there are people on Earth. 

That's over 7 billion!


2. Why is soil important?

Healthy soil supports a web of life, from microscopic bacteria and fungi to the larger worms and slugs, all these soil creatures play a vital role in breaking down organic matter…

What happens to leaves when they fall?  plants when they die back?  creatures when they die?

All this dead material is food for soil creatures, as they eat it and break it down it provides food or nutrients in a form that plants can take up.  Soil creatures burrow through the soil creating spaces, this improves the structure of the soil, helps plant roots get air and helps water to drain through the soil so it doesn’t get water logged. Smaller spaces between particles hold water for plant roots to take up

Can you list a few things that soil provides?

  • a habitat for living creatures – a ‘home’
  • food for plants to ‘eat’
  • air for plants to ‘breathe’
  • water for plants to ‘drink’
  • support to anchor plants roots


3. Can humans change soil?

We can quickly improve the soils health and make it a better place to live for soil creatures and plants by adding compost.  Compost is organic material (e.g. dead plants) and food waste that has already been broken down.   

We can also easily damage the soil though chemicals, compaction, erosion or flooding.  This damage destroys the environment for soil creatures so they can no longer live in the damaged soil – they may have no air or nutrients.  Badly damaged soil can take many, many years to be repaired or at worst it can be irreversible. 

So we can all play our part in maintaining a healthy soil environment by making our own compost. A quick way to do this is to create a worm composter or wormery.

Fascinating Fact: worms have 5 hearts, no teeth, no eyes, if you cut a worm in two it will die! it's a myth that it will survive as two worms


4. Making a worm composter

Check out our instruction sheets Worm Composter  - don’t waste your waste’ (will open in a new tab)  for a fun outdoor session on making a worm composter with your school or class. 


Encourage your class and your school kitchen to recycle their food waste and use the nutrient rich compost in your school garden

Worm Squirm:

Q. what's worse than biting into an apple and finding a worm?  

A: biting into an apple and finding half a worm!


We cover all this and much, much more during our Going Underground workshop. Take a look at this and our many other workshops on our website.  Call us on 01621 788326 for an informal chat about how we can help provide curriculum rich, science and design activities for your class. 

Our workshops can also help with your

  • School Garden
  • Eco-Schools awards
  • Pupil Premium investment