Science · Colouring and writing worksheet
How a Fossil Is Made: Free KS2 Worksheet (Ages 7 to 8)
This free printable worksheet helps children aged 7 to 8 understand how fossils are formed — a key part of the Year 3 science unit on rocks. The single illustration shows the same fish at four stages, from lying on the seabed to becoming a fossil hidden in rock, so children can see the process unfold across millions of years.
Children colour the picture and then write the steps in their own words. The page is designed to print onto one A4 sheet, making it easy to use at home or in the classroom with no preparation beyond a printer and some colouring pencils.
How a Fossil Is Made
Free Science worksheet · Ages 7 to 8
Activity 1
Colour the four pictures to show how a fossil is made. Use blue for the sea, brown for the mud and sand, and grey for the rock.
- Colour the sea around the fish blue in the first picture.
- Colour the layers of mud and sand brown as they settle on top.
- Colour the thick layers of rock grey once the fish is buried.
- Colour the cliff face in the last picture to show where the fossil is found.
Activity 2
Write the four steps that show how a fossil is made. Use the word bank to help you.
Step 1: What happens to the animal at the start?
Step 2: What happens to the soft parts of the animal?
Step 3: What buries the hard parts?
Step 4: What happens over millions of years?
How a Fossil Is Madeowee.worldAnswer key
- Step 1: What happens to the animal at the start? — The animal dies and sinks to the seabed.
- Step 2: What happens to the soft parts of the animal? — The soft parts rot away, leaving the hard parts such as bones.
- Step 3: What buries the hard parts? — Layers of mud and sand settle on top and bury the hard parts.
- Step 4: What happens over millions of years? — The layers turn to rock and the buried shape becomes a fossil.
What this worksheet teaches
This worksheet introduces the idea that fossils are the preserved remains or traces of living things, formed over a very long time. Children learn the simple sequence at the heart of the Year 3 curriculum: an animal dies and sinks to the seabed, its soft parts rot away, layers of mud and sand bury the hard parts such as bones or shells, and over millions of years the buried shape slowly turns to rock. The four-stage picture gives children a clear visual model so they can talk through and write about each step with confidence.
Why fossils sit within the rocks topic
In the National Curriculum, fossils are taught as part of the wider Year 3 unit on rocks. This is because most fossils are found in sedimentary rock, which itself forms from layers of mud, sand and other material that build up and harden over time. Linking the two ideas helps children understand why fossils are usually found in layers and why deeper layers are older. It is worth reminding children that only hard parts — bones, teeth and shells — tend to survive, while soft parts almost always rot away, which is why we so rarely find fossils of jellyfish or worms.
Key vocabulary to introduce
Building the right vocabulary helps children explain the process clearly. Useful words for this topic include fossil (the remains or trace of a living thing preserved in rock), sediment (small pieces of mud, sand and rock that settle in layers), layer (a band of rock or sediment), decay or rot (when soft parts break down), and millions of years (the very long time the process takes). Encourage children to use these words when they write their answers rather than relying on everyday phrasing.
How to use this sheet at home or in class
Begin by talking through the picture from left to right, asking children to describe what is happening in each stage before they write anything. They can then colour the scene — perhaps using blue for the sea, brown for the mud and grey for the finished rock — which reinforces the idea that the surroundings change as time passes. Finish with the writing task, where children put the four steps into their own words. To extend the activity, ask why we mostly find the hard parts of animals and what a fossil can tell us about creatures that lived long ago.
Frequently asked questions
How are fossils formed for KS2 children?
In simple terms, a fossil forms when an animal dies and sinks to the seabed, its soft parts rot away, and layers of mud and sand bury the hard parts such as bones or shells. Over millions of years the layers harden into rock and the buried shape becomes a fossil. This is the explanation set out in the Year 3 science curriculum.
What age group is this fossils worksheet for?
It is written for children aged 7 to 8 (Year 3), the stage at which fossil formation is introduced in the National Curriculum as part of the rocks topic. Confident younger children or those revisiting the topic in Year 4 may also find it useful.
Is this fossil worksheet free to print?
Yes. The worksheet is completely free to download and print. It is laid out to fit on a single A4 page so you only need a printer and some colouring pencils — no login or payment is required.
Why are only the hard parts of an animal fossilised?
Soft parts such as skin, muscle and organs usually rot away quickly after an animal dies. Hard parts like bones, teeth and shells are far more likely to survive long enough to be buried by sediment and turned into rock, which is why most fossils show only these hard parts.
How long does it take for a fossil to form?
Fossils form very slowly, usually over millions of years. The sediment must build up, bury the remains and then gradually harden into rock, which is a process that takes far longer than a human lifetime.
Curriculum links
- Year 3 Science (Rocks): describe in simple terms how fossils are formed when things that have lived are trapped within rock.
- Year 3 Science (Rocks): compare and group together different kinds of rocks on the basis of their appearance and simple physical properties.
- Working scientifically (Lower KS2): use straightforward scientific evidence to answer questions or to support their findings.
- Working scientifically (Lower KS2): record findings using simple scientific language, drawings and labelled diagrams.
Made by The Owee education team. Updated 02/06/2026. Free to print and share.
More learning, made playful
Owee turns topics like this into age-right quizzes for children aged 5 to 10, with a treehouse that grows as they learn. Three subjects are free, forever.
Get Owee free