What should a child experience during a really good primary science lesson?
There might be practical work, discussion, diagrams, questions, books and plenty of opportunities to talk about science. But none of these things, on their own, tell us whether children are actually learning.
The more useful questions are:
What do we want children to know? How does that knowledge build on what they already know? And what do we want them to be able to do with it?
For me, these questions are at the heart of high-quality primary science.
Start with what children already know.
Children already have ideas about the world around them. Some of those ideas will be scientifically accurate. Others will be partly correct, or based on something they have seen at home.
Before teaching a new idea, we need to find out what children already understand
Take sound in Year 4. Before children can investigate how sound travels through different mediums, they need to be able to identify those mediums as solids, liquids and gases. That understanding comes from their work on states of matter.
If that earlier knowledge is not secure, introducing new vocabulary and processes can become much harder.
A quick retrieval question, discussion or short quiz can give a teacher useful information about where to start.
Build new knowledge on what came before
Science is full of ideas that depend on other ideas.
Children cannot understand food chains particularly well if they do not understand what plants need to grow. Understanding how the Earth moves through space helps children make sense of day and night. Understanding shadows depends on ideas about light travelling from a source.
This is why progression matters.
We need to think beyond the individual lesson and ask what children have learned before this unit, and what they will need this knowledge for later.
Teachers should be able to see how the knowledge in one unit connects to what children have learned before and what they will learn later.
Teach the vocabulary, and give children chances to use it
Science has a lot of specialist vocabulary, and children need to learn how to use it accurately.
But putting words on a vocabulary list is not the same as teaching them.
If children are learning about forces, for example, they need opportunities to hear, discuss and use words such as force, friction, contact and surface in meaningful contexts.
Vocabulary should become part of the science children are doing and talking about. It also needs to be revisited, so a word introduced in one lesson does not disappear when the unit ends.
Knowing a scientific word is not the same as understanding the idea behind it, so children also need opportunities to explain their thinking.
Why does a shadow change size?
Why does ice melt?
Why do some materials conduct electricity?
Why does a plant need light?
As children explain their ideas, teachers can identify what they understand and where misconceptions remain. Sometimes a child’s explanation tells us much more than a worksheet ever could.
Make practical work purposeful
Primary science should involve practical experiences. Children need opportunities to observe, measure, compare, investigate and handle materials and equipment.
But practical work needs a purpose.
If children are investigating which materials are the best thermal insulators, the practical should help them answer a scientific question. They should know what they are comparing, what they are measuring and what the results might tell them.
The practical activity is not the learning by itself. It is there to help children develop and apply scientific knowledge.
Working scientifically develops over time. Children should gradually learn how scientists ask questions, make observations, measure, compare, identify patterns, gather evidence and communicate what they have found.
A Year 1 child might make careful observations of plants. By upper Key Stage 2, children should be able to plan more complex investigations, identify variables, take measurements and consider how reliable their evidence is.
The expectation should develop as children move through the school.
Revisit important knowledge, and check it has stuck
Science contains a lot to remember.
Children need opportunities to return to important knowledge regularly, rather than learning it for an end-of-unit test and then moving on.
Retrieval questions can bring previous learning back into the classroom and help children make connections between different areas of science. For example, a question about why a plant needs light can revisit learning from an earlier unit while preparing children for later learning about photosynthesis.
This helps children see science as a body of connected knowledge, rather than a series of separate topics.
Assessment in primary science does not have to mean a test at the end of every unit. Questions, discussions, retrieval activities, practical work and children’s explanations all give teachers information about learning.
The important thing is to use that information.
If several children think that heavier objects fall faster, for example, that misconception needs addressing. Simply moving on because the lesson has finished does not mean the learning has happened.
Good assessment helps teachers decide what needs to be revisited, explained differently or extended.
So, what does high-quality primary science look like?
It looks different from classroom to classroom, but there are some common features.
Children are building knowledge over time. They are connecting new learning with what they already know. They are learning scientific vocabulary and using it accurately. They are carrying out practical work for a reason. They are developing their ability to work scientifically. They are revisiting important ideas and explaining what they understand.
Most importantly, the individual lesson belongs inside a bigger sequence.
That is the thinking behind HEP Science.
HEP Science is a complete primary science curriculum for Years 1 to 6, designed so that knowledge, vocabulary, practical science and working scientifically develop progressively across the primary years.
Teachers have access to the lessons, pupil resources, practical guidance, retrieval and assessment materials, progression information and additional support they need to teach the curriculum well.
The aim is to bring the different parts of primary science together in a clear, coherent sequence, so that teachers have less to prepare.
A useful starting point for your own science curriculum
If you are reviewing science in your school, start by asking these questions:
- What do children already know before each unit?
- What knowledge do children need before they start, and how will they build on it later?
- Which scientific vocabulary needs to be explicitly taught?
- What practical experiences do children need?
- How does working scientifically develop from Year 1 to Year 6?
- Which important ideas are revisited?
- How do we identify and address misconceptions?
- How do we know what children have actually learned?
I’ve put these questions together into a Primary Science Quality Checklist that you can use when reviewing your own curriculum or planning.
And if you are looking for a complete, sequenced primary science curriculum rather than building all of this from scratch, you can find out more about becoming a HEP Science subscriber here. All HEP Member Schools get free access to HEP Primary Science curriculum resources here.

About the Author
Brenda Hayles
Brenda Hayles is an award-winning teacher, former senior school leader and the author of the HEP Science Curriculum from Haringey Education Partnership (HEP). She has over 25 years of teaching and leadership experience in London schools. She holds an MSc in Education and Health Promotion and an Institute of Leadership and Management (ILM) Level 5 in Leadership.
Brenda has built HEP Science as a complete online curriculum, ready to use from day one. Everything for each unit sits in one place, from lesson slides to quizzes and assessments. She draws the illustrations herself, so every resource has the same bright, clear look.
She is also a Canva Education Specialist Content Creator and regularly sits on a Bett panel for science content experts.

