You can’t. ChromeOS doesn't support it natively anymore. For a long time, the only way to play AJ Classic on a Chromebook was the Puffin Browser . Puffin is a cloud-based browser that processes Flash content on its remote servers and streams the video to your Chromebook.
But here’s the modern dilemma: Your household runs on Chromebooks.
If you have a child who loves animals, trading rare items, or solving puzzles, chances are you’ve heard of Animal Jam Classic (AJ Classic). This nostalgic, browser-based MMO has been a staple for over a decade.
Play Wild is the modern, mobile-friendly version of AJ. It was rebuilt without Flash. You can download it directly from the onto your Chromebook (most 2020+ Chromebooks support Android apps).