Web-based training programs commonly capture data reflecting e-learners' activities, yet little is known about the effects of this practice. Social facilitation theory suggests that it may adversely affect people by heightening distraction and arousal. This experiment examined the issue by asking volunteers to complete a Web-based training program designed to teach online search skills. Half of participants were told their training activities would be tracked; the others received no information about monitoring. Results supported the hypothesized effects on satisfaction, performance, and mental workload (measured via heart rate variability). Explicit awareness of monitoring appeared to tax e-learners mentally during training, thereby hindering performance on a later skills test. Additionally, e-learners reported less satisfaction with the training when monitoring was made salient.