Attention Deficit / Hyperactive Disorder (ADHD), although classified as a neuro-developmental disorder, is diagnosed based on observed behavioral outcomes alone. Given that some brain attentional networks involve circuits that control the eye pupil, we monitored pupil size from ADHD-diagnosed children and from control children, during a visuospatial memory task. We present here the full data set, consisting of pupil time series for each trial and subject, and the corresponding behavioral data. There are data from 50 subjects: 22 control and 28 ADHD-diagnosed children. There are also data from a subset of 17 ADHD children that performed the task twice, on- and off-medication. We describe in detail how the data was collected and processed. Recent evidence from different model systems has shown that pupil size provides a window into the functioning of diverse brain networks, including neuromodulatory circuits, which are usually hard to monitor noninvasively. In this context, the data set can serve as a resource to analyze dynamic pupil changes as a function of behavior, reflecting neurocognitive processes.