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
Help them understand.
Not just memorise.
Visual GCSE Maths lessons to help your child understand difficult topics and revise for exams. Explanations they can pause and replay, with questions to put the method into practice.
Watch the free lessonsFree preview. Three lessons available now. No account needed.
GCSE MATHS, EXPLAINED VISUALLY01 / ALGEBRA
See what changes when the equation changes.
WATCH THE FREE LESSONS
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.
GCSE LEARNING & EXAM REVISION
Understand the topic.
Prepare for the exam.
01
Watch the idea
Animations show how a method works. Pause or replay a step whenever it helps.
02
Have a go
Try a question without the answer in front of you. Use a hint if you get stuck.
03
Check the method
Follow a worked solution and see which step needs another look.
For learning throughout GCSE and focused Year 11 revision. The full service will include practice exams with links from questions to videos on the relevant topic, so students can revisit the parts they need help with.
TRY THE APPROACH
A question to work through.
Sample Practice · Pythagoras
GCSE Foundation & Higher
QUESTION 1 OF 3
Find the longest side
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.
BEFORE YOU START
Questions from parents.
What can my child use 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?
It is being designed for independent study, with explanations students can replay and questions they can work through at home. A tutor can adapt to an individual student in ways a prepared lesson cannot. Try the free examples to judge whether this approach suits your child.
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 child’s 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.
Can teachers use the preview?
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.
Can students use captions or change the video speed?
Each player includes English captions, playback controls and full-screen viewing. Available speed controls depend on the browser. You can also switch between light and dark mode using the button at the top of the page.
HELP SHAPE EXPLAINSTEM
What would make this useful for your family?
We’re building ExplainSTEM around clear visual lessons and plenty of practice. After trying the demo, tell us what works and what you would want before considering a subscription.
Parents, students, teachers and tutors are all welcome to share their thoughts.
No name or email needed. Please leave out children’s names, schools and other personal details.
For a question that needs a reply, contact Alex by email.