If you have a student that struggles with time management, they may need a visual time to help. Visual timers can also be used to help keep students on task and for some students they are motivating.
Timers can be a stand alone device such as the Time Timer (https://www.timetimer.com/). They are also integrated into Android & iOS devices, and can be visual as well. You can also do a quick search in Google for a timer if you want to have it on a Google Chrome compatible device or to share it up on a smart board for the whole class to see.