Built by a high school student who almost did not pass.

I am a high school senior at ACCEL Middle College, which lets me dual‑enroll at the community college a few miles from my house. Some days I am in a high school classroom and some days I am in a college lecture hall. The two settings have one thing in common, which is that for most of my life neither of them taught me how to learn.

I was diagnosed with ADHD at nine. My GPA, by junior year, was a 2.5. I was on my second attempt at Calculus and the midterm came back as a 65.

I had studied. I had gone to office hours. I had done the practice problems. I stared at the page on the walk home and could not figure out what had happened. If I failed this attempt, I would have to take Calculus a third time.

I had a few weeks left in the semester. I decided to do it differently. I went looking for cognitive science papers because I had run out of other ideas.

The papers said the techniques most students use, rereading and highlighting and summarizing, are rated low utility by the field. The two techniques rated high utility are practice testing and distributed practice. They are taught almost nowhere.

The students who get them get them through paid private tutors who ask them questions every night. That is what tutoring is, mostly. A second mind, in the room with you, drilling you on what you almost know.

The rest of us are handed a textbook and a quiet room and told to study harder.

I built a method out of necessity. Take the chapter. Break it into the smallest pieces. Try to explain each piece in your own words, without looking. Find out what you missed. Do it again with what you missed in mind. Keep going, piece by piece, until you can produce every concept on demand.

The final of that same retake came back as a 97. From a 65 to a 97 in a few weeks. I had almost failed Calculus a second time; I had not.

Then I used the same method for U.S. Government, where the hardest test of the semester, the one most students failed, came back as a 42 out of 47, second highest in the class. Every question I had used the method on, I got right. Every question I had not used the method on, I got wrong.

I used it for philosophy. I used it for psychology. I used it for biopsychology. The grades came back the same way. I had spent twelve years thinking I was bad at school. The grades had been data about a method I had never been given, not data about me.

I built Acacia so the same method I used by hand could run on any chapter you paste. It reads the chapter. It breaks it into small lessons. It asks you to explain each one back. It tells you, in four colors, what you got right and what you missed. It does not let you move on until you can produce the concept on your own.

I made it free because the only reason this method has been the privilege of wealthy students for two thousand years is that the second mind asking the questions has been a paid human tutor. The second mind no longer has to be a paid human. So I made it not one.

I built this out of need. Then I learned, slowly, that a lot of other students need it too.