They don't wish to demonstrate their lack of skill through public, mistake-ridden practice. But neither are they allowed to withdraw from the situation due to mandated attendance requirements. They keep their place in line, but are able to avoid taking their turn. They run up and down the field in team sport activities, but rarely contact the ball or influence play. The developmentally appropriate response to this pattern of nonparticipation is to recognize individual differences between students and develop activities that can be adapted to the individual needs of the students.
Tasks are planned activities or skills to be taught.
A task is the basic unit of instruction. Extensions are variations of the basic task. Extensions are usually progressive in nature, from easier to more difficult. An extension may be as simple as asking students to perform a skill with a different body shape, at a different speed, or maybe with a partner. Refinements are cues used by the teacher to focus students' attention on a particular aspect of the task.