Chromebooks are not built for gaming, but you can achieve a smooth 60 FPS in Eaglercraft by optimizing your browser settings:
Change the look and feel of the game by loading custom texture packs. How to Play Eaglercraft Unblocked 1.12.2
Set your username, choose or upload a skin, and adjust your video settings based on your device's hardware.
Save your progress directly to your browser's local storage.
Running a 3D sandbox game entirely within a browser tab can sometimes cause frame drops or lag, especially on low-end school Chromebooks. Use these optimization tips to achieve a smooth 60 FPS: In-Game Video Settings