For infants, observation cycles are 15 minutes, while for PreK-3, they are 20 minutes. Each age group also includes a roughly 10-minute coding period after each observation cycle. For PreK-3 observations, plan for 30 minutes per cycle—20 minutes to observe and 10 minutes to code. If an interruption occurs before 10 minutes of observation, the cycle must be redone. However, if the interruption (e.g., a fire drill) happens after 10 minutes, the cycle can be scored and used. Hope this clarifies things!
Best,
Rachel