01 / GEOMETRY
Pythagoras’ Theorem
See how the squares on a right-angled triangle fit together, then use the relationship to find a missing side.
A first look · GCSE Maths
Understand GCSE Maths.
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See the maths explained through animation, then try it yourself. Pause, replay and practise at your own pace, whether you’re learning a topic or revising for exams.
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GCSE MATHS, EXPLAINED VISUALLY01 / ALGEBRA
See what changes when the equation changes.
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See how we explain it.
02 / GEOMETRY
Angles in a Semicircle
Find out why an angle drawn from the ends of a diameter is always 90°, and see how to spot it in a question.
03 / ALGEBRA
Quadratic Graph Transformations
Watch a quadratic shift left, right, up and down. Connect each change in the equation to what happens on the graph.
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A question to work through.
Pythagoras
QUESTION 1 OF 3
Find the longest side
The two shorter sides are 6 cm and 8 cm. Find x, the length of the hypotenuse.
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a² + b² = c²
Try it on paper first.
Identify the longest side, write the equation and substitute the lengths. The hint and solution are here when you need them.
Watch the explanation ↑These three original questions demonstrate the planned practice format. The full question library is still being built.
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Questions about ExplainSTEM.
What can I try now?
All three videos and the three sample practice questions on this page are free to try. No account or payment is required.
Will ExplainSTEM help with Year 11 exam revision?
Exam preparation is part of the plan, alongside learning individual topics. We’re planning practice exams with links from questions to relevant video explanations. Practice exams are not available in this demo yet.
How is this different from watching a revision video?
The planned service brings visual explanations, worked examples and structured practice together by topic. This preview lets you try the explanation and practice format before the larger library is ready.
Does ExplainSTEM replace a tutor?
ExplainSTEM is being designed to help you study independently, with visual explanations you can replay and questions to check your understanding. A tutor can give individual feedback that a prepared lesson cannot. Try the free demo to see whether this way of learning works for you. Parents and carers can try it too before considering the full service.
What subjects and levels will be covered?
This demo covers GCSE Maths. Pythagoras is relevant to Foundation and Higher; circle theorems and quadratic graph transformations are aimed at Higher study. Check your exam specification for topic coverage. GCSE Physics, Chemistry and A-level content are planned, with no release date yet.
How much will it cost?
The preview is free. Pricing for a future paid service has not been decided. There is no subscription or checkout on this site.
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Teachers and tutors are welcome to show the preview during teaching and send feedback. Please link to ExplainSTEM rather than re-uploading or selling the videos.
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BEHIND EXPLAINSTEM
Why I’m building
ExplainSTEM.
I’m Alex. I achieved grade 9s in all my STEM GCSEs and I’m now studying for a master’s in engineering at the University of Manchester.
I’m building ExplainSTEM to help you aim for the grades you want without the cost of regular tutoring. Visual explanations and plenty of practice should give you room to learn at your own pace, whether you need longer on a topic, prefer seeing how it works or want to keep practising between lessons.
This demo is an early step. Your feedback will help shape the full GCSE Maths service.
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