The undertreatment of postoperative pain in children remains a critical problem. Only recently have clinical trials begun to evaluate the efficacy of pharmacologic interventions in the management of postoperative pain beyond the immediate postoperative recovery period and after discharge home following tonsillectomy. Given the fact that approximately 50% of pediatric surgeries are done on an outpatient basis, this study has the potential to improve the home pain management of thousands of children. This study is one of the first to evaluate in a systematic fashion the use of an around-the-clock dosing of a weight appropriate dose of a nonopioid/opioid combination analgesic compared to as needed dosing. Because the study will evaluate the effectiveness of both a behavioral intervention and two different pharmacologic interventions, it will provide important information that should have a direct clinical application in the management of children's pain.