These simple cards are a great way to build up your students' stamina for independent work. I have included a description of how I use them in my class to help us work towards workstations.
Each card represents a period of time in minutes. Each day we work towards the next card that is in line. If the "5" card is in front, we work towards working independently for 5 minutes. If we can successfully work for 5 minutes independently, the next day we would word for 6 minutes.