Sleep deprivation and fatigue are major players in arousal.
For me it was the universe. For my 3.5 year old daughter, Mr. Rogersā Neighborhood is the carrot. She will happily do a 45 minute piano lesson and pick up her toys for the privilege of seeing a half hour of Mr. Rogers.
The following internet site in the Notes describes how to make a motivating web page but it relates nicely to motivation in my opinion.
Sleep Deprivation and/or Fatigue are major factors in arousal.
Some high school and college students work several jobs while they attend classes and find it difficult to maintain a high level of perceptual energy in school despite their high motivation to do so.
For kids, the danger, in my opinion, is TV. The problem is that it can emulate the sleep patterns of the brain without providing the benefits.
Hence, children can watch mindless shows late into the evening, only to find real sleep inevitable in the classroom the next day in school.