Objective:To determine whether stabilizing serum glucose,via introduction of an insulin pump,improves classroom attention among children with type-1 diabe tes mellitus.Study design:Four boys having type-1 diabetes mellitus with unst able serum glucose were observed in their classroom for 10 baseline days.An ins ulin pump was placed and serum glucose stabilized,and they were then observed a gain for 10 days.A modified multiple baseline design was used to determine if i mproved on-task and off-task behavior was associated with better glycemic cont rol.Rating scales and a laboratory measure of attention,measures of secondary interest,were also administered before and after pump introduction,and potenti al improvement in individuals’scores was evaluated.Results:All boys had appar ent improvement in on-task and off-task behavior as observed in their classroo ms.Improvements were substantial,averaging 20%in on-task behavior and 34%in off-task behavior.However,no changes were detected on rating scales or labor atory measures.Conclusion:This study offers preliminary evidence that stabiliz ing serum glucose improves classroom attention,although the effect was detected only by observation of classroom behavior using highly structured techniques.C onsequently,use of direct observation techniques may be important in studying t he effects of chronic illness on classroom functioning. Objective: To determine whether stabilizing serum glucose, via introduction of an insulin pump, improves classroom attention among children with type-1 diabe tes mellitus. Study design: Four boys having type-1 diabetes mellitus with unst able serum glucose were observed in their classroom for 10 baseline days. An ins ulin pump was placed and serum glucose stabilized, and they were then observed a gain for 10 days. A modified multiple baseline design was used to determine if i mproved on-task and off-task behavior was associated with better glycemic cont rol. Rating scales and a laboratory measure of attention, measures of secondary interest, were also administered before and after pump introduction, and potenti al improvement in individuals’scores was evaluated. Results: All boys had appar ent improvement in on- task and off-task behavior as observed in their classroo ms.Improvements were substantial, averaging 20% ​​in on-task behavior and 34% in off-task behavior. Still, no changes were detected on rati ng scales or labor atory measures. Confc: This study offers preliminary evidence that stabilizing serum glucose improves classroom attention, although the effect was detected only by observation of classroom behavior using highly structured techniques. Continuing, use of direct observation techniques may be important in studying t he effects of chronic illness on classroom functioning.