In Q4 2025, Duolingo announced it would let go of $50M in bookings to reach 100 million daily active users (DAUs) by 2028; a strategy Class Central covered in detail last month.  2026 is its “investment year,” and Q1 was the first quarter of execution. So far, the plan seems to be working. The Expected Results: Low Bookings, High DAUs Duolingo is running multiple tests to improve the free experience: spoken tokens for speaking practice, Speaking Adventures for real-world conversations, and fla

Guide to the Wolfram U platform, which offers 220+ hours of courses with a free certificate of completion.

The first time you see Tailwind CSS, you might wonder whether someone accidentally pasted their stylesheet into the HTML. A single button can have a dozen classes just to control its spacing, colors, rounded corners, and hover effects. Are we really supposed to write all that? Each class does a small, specific job. Once you recognize them, you can style an element right where you’re building it, without jumping between files or thinking up another class name. The HTML gets busier, but making c

Not just courses — podcasts & webinars too, with free certificates & continuing medical education credit.

From course ratings to pricing, let’s have a look at some of the discernible trends of Udemy’s catalog.

Google offers many online courses with free certificates and badges. We’ve put together a full list.