Source: Strict Workflow – Chrome Web Store

Strict Workflow is a combination Pomodoro Timer and web filter. A Pomodoro Timer is a work/break timer, where each 25 minutes working and 5 minute break is one pomodoro. Complete 4 pomodoros and get a 15 minute break. It’s a way to help you stay on task.

Strict Workflow ups the ante by not only running the timer, but also blocking sites on the block list. Once the timer starts, there is no way to stop it without disabling the extension.

I could see this extension helping those students who are easily districted to focus and work. The time span of 25 minutes may be a little long for younger students, but you can adjust the times in the settings.