Mr. 401(k)'s Principles of Financial Literacy is a plain-English guide to money, markets, and the modern economy, written for teenagers and young adults, and for the parents and teachers who guide them.

Most money books jump straight to budgets and tips. This one starts with a better question: what is money, really? Once that clicks, the paycheck, the credit card, the index fund, and the mortgage all begin to make sense.

Every claim is shown with the math, so you never have to take a number on faith. And the book is careful never to oversell. It shows the full retirement number, then walks it back to what it is really worth in today's dollars. That kind of honesty runs through every chapter.

Teens and young adults facing a first paycheck, a first credit card, or a first benefits packet
Parents who want their kids to learn this early, instead of the hard way at forty
Teachers and homeschoolers who want a real curriculum, not another worksheet
Built in a classroom. Ready for yours.
The book is mapped, benchmark by benchmark, to the National Standards for Personal Financial Education from the Council for Economic Education and the Jump$tart Coalition, and it covers all six national topic areas: earning, spending, saving, investing, managing credit, and managing risk. With its capstone business-plan project, it works as a ready-to-teach unit, not just a reading.
A free companion guide for teachers and parents includes the full standards map, discussion prompts, and the one-page plan.
Files coming soon.
This book did not start as a book. It started as a course.
Since 2022, Petros has volunteered teaching financial literacy to middle school students, where his students know him as Mr. 401(k). The book grew out of that classroom, and the course itself remains free and openly licensed for any teacher, parent, or student who wants it.

Petros Koumantaros has spent his career helping working people build secure retirements. He has testified before the United States Senate on improving retirement savings, serves as a Governor-appointed member of Washington State's Washington Saves Governing Board, and teaches financial literacy to teenagers as Mr. 401(k). He wrote the book he wishes someone had handed him at fourteen.
If you want the head start no one gave you, start here.