| Introduction-Practice Phase | Visual Timer | Set the visual timer to approximately 30 seconds and place it in the participant’s line of sight. |
| If the participant shows excessive interest in or attempts to manipulate the timer,temporarily remove it to minimize visual distraction. |
| First-Then Picture Card | Place the First-Then picture card alongside the visual timer on the participant’s desk. Immediately point alternately to the timer and the card while verbally explaining: |
| “Stay in your seat until the red color disappears. Then you can have your favorite jelly.” |
| Intensive Reinforcement Phase | Fixed Duration Schedule(FD) | If the participant maintains seated behavior for the entire fixed interval,provide specific verbal praise (e.g., “Great job staying seated!”) followed by one piece of jelly. |
| Non-reinforcement Contingency | If out-of-seat behavior occurs at any point during the fixed interval (e.g., 2 minutes), reinforcement is withheld regardless of the participant’s seating status at the observation point. |