One credit is about 120 hours of work, or a college-level textbook finished properly, or a year of sustained study in one subject. Pick whichever of those three you can defend out loud, apply it the same way every time, and you are done.

That is the answer. The rest of this is why it is allowed to be that loose.

Where 120 hours comes from

It is the Carnegie unit, and it was invented in 1906 to sort out faculty pensions. Andrew Carnegie's foundation needed a way to decide which institutions counted as real high schools, so it defined a credit as 120 hours of classroom contact: roughly one hour a day, five days a week, for a school year of about twenty-four weeks. It was an accounting convenience. It was never a claim about how much time a human being needs in order to learn algebra.

Almost every American high school still runs on it, which is why it is the number your transcript will be read against. Six states use seat time as a legal minimum for homeschools too, in the form of required days or hours. Most do not.

So the number matters, but it matters as a shared unit of exchange, the way a dollar matters. It is not a measurement of learning.

The three defensible methods

Hours. Count 120 to 180 hours for a full credit, 60 to 90 for a half. Use this for anything that is genuinely time-based: a lab science with real lab hours, a studio art year, a sport, an apprenticeship, driver's education. Keep a log if you use this method. Not a stopwatch, a log. Weeks and rough hours, written down the same week they happened.

Text completion. One credit for finishing a standard high school text with the problem sets actually done. This is the cleanest option for math and for foreign language, because the textbook already encodes what a year is. Half a book is half a credit and no amount of enthusiasm changes that.

Demonstrated mastery. One credit for the level of work a competent high school course would produce, however long it took. This is the honest method for the kid who read all of Shakespeare in five months because he could not stop, and for the kid who needed eighteen months to get through Algebra I. Both are one credit. This is the method that makes homeschooling worth doing and it is the one that makes parents most nervous, because there is no number to hide behind.

You are allowed to use different methods for different subjects. You are not allowed to use whichever method produces the bigger number, subject by subject. That is the line, and the only person who can police it is you.

Awarding credit for a year with no syllabus

Say your kid spent a year on the American Civil War. Primary sources, a battlefield in the spring, a long argument at dinner about Reconstruction that lasted a month. No textbook, no tests.

Work backwards from the artifact. What exists at the end of it? Reading list, essays, the trip, the project. Write the course description first, describing what actually happened, in the plain register an admissions reader expects. Then look at the description and ask honestly whether it represents about as much work as a year of high school US History. If it does, that is one credit of US History. If it represents about half that, it is a half credit and you pair it with something else.

Do not invent a test to make it feel official. The description is the documentation. An admissions office would rather read "primary sources, four analytical essays, a research paper on the Freedmen's Bureau" than see a fabricated 94 percent.

Where people go wrong

Counting life as credit. Chores are not Home Economics. A family trip is not Geography. This is the stereotype that makes admissions readers skeptical of homeschool transcripts generally, and every parent who does it makes it slightly harder for the next one. If it was not deliberate study, it does not go on the transcript. It can go in the activities list, where it belongs and where it actually helps.

Inflating to look competitive. Thirty-two credits does not read as impressive. It reads as padded. Twenty-four solid ones read better than thirty-two soft ones, every time.

Retroactive precision. Deciding in senior year that ninth grade was "about 140 hours" of something. You do not remember. Nobody remembers. Write it down in June.

The part nobody tells you

You are the school. Not metaphorically, legally, in most states. The registrar who decides what counts as a credit at your local high school is a person applying a policy with judgment, and you are that person now.

That is uncomfortable in exactly the way it should be. The discomfort is the accountability, and it is doing its job. A parent who feels slightly uneasy awarding a credit is a parent awarding it honestly. The ones who should worry are the ones who never think about it at all.

The Records System includes the credit tracker we keep, a place to log hours by week without turning it into a second job, and 131 course descriptions you can edit down to the books actually on your table. Thirty-nine dollars.