How Dexter works
A suite of resources with
Rich's teaching at its heart.
Three things shape every answer Dexter gives: how Rich teaches, exactly what your exam board's specification asks for, and what Dexter learns about you as you work together.
What shapes Dexter
Built from real teaching, matched to your course.
- Rich's teachingDexter is trained on 21 years of A Level Chemistry teaching: Rich's explanations, his methods and the exam advice he gives his own students.
- Your exam board's courseDexter follows one exam board's specification exactly, AQA or WJEC. He teaches what your course asks for, without pulling you into content it doesn't need.
- How your exam asks questionsExam-style questions are written in the style of your exam board and marked against marking points, the way your exam is marked.
- YouDexter adapts to your strengths, weaknesses and preferences, and remembers what you covered, so each session starts where the last one ended.
Inside Dexter
Everything Dexter can do.
Exam questions, written for you
Fresh exam-style questions on any topic, in the style of your exam board and marked instantly.
Tests, built for you
Choose your topics and Dexter writes you a test, then marks it against the marking points.
Flashcards
Quick-fire cards on any topic, made for your course, to lock in the key facts and definitions.
Readiness tracker
A readiness score for every topic, built from the questions you actually get right.
Past papers, marked
Input your past paper results and see how you did on every sub-topic.
Remembers your last session
Dexter recalls what you covered and where you got stuck, so you pick up where you left off.
Molecules, drawn for you
Ask about an organic molecule and Dexter draws its structure and gives you its name.
Diagrams that move
Mechanisms, curves and structures build step by step as Dexter explains them.
Rich's videos, when they help
When one of Rich's lesson videos explains it best, Dexter offers it to you.
Interactive tools, built in
Rich's interactive tools open right inside Dexter, including Organic Pathfinder, just for members.
Study scheduler
Tell Dexter when your test is and what it's on, and he'll put a personal study schedule together.
Weekly coaching sessions
Big topics, exam technique and revision strategy with Rich every week. Submit a question any time.
How he teaches
Step by step, the way Rich teaches.
Dexter explains one idea at a time and asks you questions back, so you understand it well enough to do it yourself in the exam. This is a real reply from Dexter.
DexterTeach me how electrophilic addition works
Electrophilic addition is the key alkene reaction — and once you've got the mechanism, all five versions of it follow the same pattern.
The big idea: the C=C double bond has a region of high electron density above and below the carbon atoms. Electrophiles — electron-hungry species — are attracted to that. The π bond breaks, both electrons go to the electrophile, and a new bond forms on the other carbon.
Here's the mechanism for the simplest case — ethene + HBr:
How he knows you
Progress built on real evidence.
Every question you answer feeds your readiness for that topic. Dexter uses it to choose what to practise next, and you can see it for yourself on your progress page.
The teacher behind him
Rich is the real teacher behind every interaction with Dexter.
- Rich trained Dexter using his knowledge and exam expertise
- Safeguarding is built in: anything worrying is flagged straight to Rich
- Students can check in with Rich directly in his weekly coaching sessions
Free tools
Start with one of Rich's free tools.
Build an atom, graph a trend or rotate a molecule in 3D. Free to use, with no login.
FAQs
Questions, answered.
Does Dexter just give answers?
No. He teaches step by step and asks you questions, so you understand it well enough to do it yourself in the exam.
Which exam boards does Dexter cover?
AQA and WJEC A Level Chemistry. Dexter teaches to your board's specification and question style. Dexter for AQA is live now. Dexter for WJEC is launching with the new website.
Does Dexter remember me?
Yes. Dexter recalls what you covered, where you got stuck and what's coming up. Your profile stays, even after the trial ends.
Where do my readiness scores come from?
From real evidence: the questions you actually got right on each topic. The lowest bars show you what to work on next.
Try Dexter today. Ask him
about the topic you're stuck on.
Free for 14 days, no card required.
