Skip to content
Kolu

Any subject, taught from what you already know.

Kolu finds the edge of what you know, teaches from there, and calls a skill mastered only once it lasts.

For example

Start free. No card needed.

Cardiovascular physiology

A clot blocks the marked artery. Which wall of the heart loses its blood supply?

Engraving of the front of the heart, showing the right and left ventricles and the coronary arteries running over them.
The front of the heart and its coronary arteries. Gray’s Anatomy, 1918.

How Kolu teaches

  1. 01

    Start from a sentence

    Name a subject, a goal or an exam. Or take a skill check that finds the edge of what you know.

  2. 02

    See the map

    The subject as skills in the order they build on each other: what you have, what is next, what is missing.

  3. 03

    Learn one step at a time

    Each session mixes review, repair of a gap, one new idea and a problem in an unfamiliar setting.

  4. 04

    Keep what you learn

    A skill is mastered after varied answers, without help, across days. Kolu brings it back before it fades.

The material is the method.

Notation set properly, figures you can work with, and a map of what leads to what, in every subject.

Fig. 1 · Biology

  1. Glucose

  2. Glucose-6-phosphate

  3. Fructose-6-phosphate

  4. Fructose-1,6-bisphosphate

  5. 2 × three-carbon sugars

Phosphofructokinase-1. The committed step. Slowed by ATP and citrate, sped up by AMP: the cell’s energy gauge.

The investment phase of glycolysis. Select a step.

Fig. 2 · Finance

present value equals the sum over t from 1 to n of C over 1 plus r to the t
YearFactorToday
10.952$95.24
20.907$90.70
30.864$86.38
Worth today$272.32
Three payments of $100, discounted at 5%.

Fig. 3 · Linear algebra

VectorsSystemsSpanLinear mapsDeterminantsEigenvalues
Your map. Each skill opens the ones it points to.

Mastered means it lasted.

One right answer is evidence, not mastery. Kolu waits for answers in more than one form, without help, and again after time away.

day 1day 7day 14day 21a week awayFirst right answerA different kind of questionNo hintsStill right after a week awayLearningSolidMastered

From a first fraction to a graduate proof.

Browse the library

Mathematics

Arithmetic · Fractions and decimals · Pre-algebra · Algebra

Computer science

Programming basics · Data structures · Algorithms · Web development

Physics

Mechanics · Waves and oscillations · Thermodynamics · Electricity and magnetism

Economics and business

Personal finance · Microeconomics · Macroeconomics · Accounting

History

Ancient history · Medieval history · Early modern history · American history

Chemistry

Atoms and the periodic table · Chemical bonding · Reactions and stoichiometry · States of matter and gases

Biology

Cells · Genetics · Evolution · Ecology

Medicine and health

First aid · Nutrition · Exercise and fitness · How the body works

Psychology

Introduction to psychology · Cognitive psychology · Developmental psychology · Social psychology

Philosophy

Introduction to philosophy · Logic and critical thinking · Ethics · Ancient philosophy

Literature

Reading well · Writing · Poetry · The novel and short story

Languages

English as a second language · Spanish · French · German

What will you learn first?

For example