Online MCAT course · all 4 sections
The complete MCAT course. Every mistake explained.
The Pass includes
See how a mistake gets corrected.
A real question from the course. Pick an answer.
Bio/Biochem · from the course
Glutamic acid has pKa values of 2.2 (α-carboxyl group), 4.3 (side-chain carboxyl group), and 9.7 (α-amino group). What is its isoelectric point (pI)?
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What you get
A complete MCAT course, not just a question bank.
Everything below comes with one Pass, for all four sections: Bio/Biochem, Chem/Phys, Psych/Soc and CARS.
Practice questions
Original passages and discretes. Every wrong choice explained, its trap named.
Full-length exams
230 questions each, in test-day order, timed.
Chapters, in study order
A day-by-day plan to your test date that moves your weak spots earlier.
Flashcards
Spaced review, so facts come back before you forget them.
Trap Bank drills
Short drills on the traps that catch you most.
Interactive labs
Buffers, enzymes, neurons, spectra and CARS X-ray. Guess, then watch it happen.
11 full-length exams: 2 fixed forms + 9 built fresh from questions you’ve never seen. Timed like test day; results show % right, time and the traps that cost you points. No scaled score: these exams are not calibrated to AAMC.
- Every miss back on day 1, 3 and 7
- X-ray lens on every CARS passage
- 83 passages open with a 30-second lesson
Look-alikes
Two molecules. One number. One reason.
The 30-second 3D lessons from our reels: two look-alikes side by side, the real size of the difference, then why. Each card opens three course questions on the same idea.
Acetic acid vs ethanol.
1011×more acidic.
Three fluorines on acetic acid.
34,000×more acidic.
HF vs HCl.
1010×weaker acid.
Labs
Guess first. Then watch it happen.
Built on the real equations. Change one number and the curve, the molecules and the readout move together. Try this one.
Buffer Lab · Henderson–Hasselbalch
Your blood sits at pH 7.4. The CO₂ / HCO₃⁻ pair has pKa 6.1.
For every CO₂, how many HCO₃⁻? Guess before you touch anything.
pKa values: acetic acid 4.76, dihydrogen phosphate 7.21, ammonium 9.25 (OpenStax Chemistry 2e, appendices); CO₂ / HCO₃⁻ 6.1, the value used for blood.
CO₂
HCO₃⁻
Reviews
From students using the Pass.
The Pass
One payment. Every section. Yours to keep.
No subscription, no renewal, no account to create first. Pay on Gumroad, your key arrives by email, paste it in the course. New passages come on the same key at no extra cost.
Founding priceThe Pass
$299Until November 30. Then $600.
One payment, no subscription.
Use it alongside the official AAMC materials: AAMC tells you your score, Red Pen Prep tells you why you missed.
- 3,122 original questions, every wrong choice explained
- 11 full-length exams, 230 questions each
- The red pen: every trap named, the deciding line marked
- A day-by-day plan across 37 chapters
- 2,052 flashcards and 155 Trap Bank drills
- 6 interactive labs and 30-second 3D lessons
- Every miss back on day 1, 3 and 7
- New passages added at no extra cost
Checkout on Gumroad. Your key arrives by email.
If it isn’t helping, reply to your receipt email, or DM @redpenprep on Instagram within 30 days and get every dollar back. No questions asked. Email support
Not sure yet? Try 10 questions first
Questions
Before you decide.
Anything else? Reply to your receipt email, or DM @redpenprep on Instagram.
Who is it for?
Pre-meds preparing for the MCAT who know much of the content but still lose points on questions they could have gotten right. It covers all four sections, so it works as your main course or next to the official AAMC material.
What exactly do I get?
3,122 original practice questions across Bio/Biochem, Chem/Phys, Psych/Soc and CARS, each wrong choice explained with its trap named. 11 timed full-length exams of 230 questions. A day-by-day study plan across 37 chapters that moves your weak spots earlier. 2,052 flashcards with spaced review, 155 Trap Bank drills, 6 interactive labs, and 30-second 3D lessons.
How is this different from a question bank?
Most banks tell you the right answer. Red Pen Prep shows why the wrong one looked right: each wrong choice is tagged with the trap it sets, and the line that decides the question is marked. Every miss comes back 1, 3 and 7 days later, so the same trap stops costing you points.
Can I try it before I buy?
Yes. Take the 10-question diagnostic on this site to see your score and the traps that cost you points, or open CARS passage 001 with its full correction. Neither needs an account.
Who writes the questions?
They are original questions written for Red Pen Prep and mapped to the AAMC content outline. Each one is solved again against its answer key and its explanations are checked before it goes into the course. Every correction has a “Report an error” link: a reported question is checked and, if needed, fixed in the next update on the same key.
Is this official AAMC material?
No. These are original passages and questions written for Red Pen Prep, and the trap names are a teaching tool, not an official AAMC list. Use the official AAMC practice exams as well.
How do I get access after paying?
Checkout is on Gumroad. Your key arrives in the receipt email. Open redpenprep.pages.dev in Safari or Chrome (not inside the Instagram app), tap Log in and paste the key.
How long do I keep access?
For good. One payment, no subscription. Your key never expires, and new passages come on the same key at no extra cost.
Which devices does it work on?
Use it on your phone, tablet and laptop: up to 3 devices per key, in any recent browser. Nothing to install, and your progress moves between devices in one file.
What if it isn’t helping me?
Reply to your receipt email (or DM @redpenprep on Instagram) within 30 days of purchase and you get a full refund. No questions asked. Once the refund is issued, the key stops working.
Will the price go up?
Yes. The founding price ends November 30. After that, the Pass is $600.