In this paper, we develop a mobile scaffolding-aid-based bird-watching learning system, which aims to construct an outdoor mobility-learning activity under the up-to-date wireless technology. The proposed bird-watching learning (BWL) system is designed on the wireless mobile ad-hoc network. In the BWL system, each learner device has PDA (personal digital assistances) with a Wi-Fi (IEEE 802.11b) card, within a WLAN environment. Specially, the BWL system contains a mobile learn sheet sub-system, which integrates the scaffolding-aid learn model into the BWL system. Finally, we conduct a formative evaluation to provide statistical results, which is evaluated for the following two purposes; (1) to explore the possible roles and scaffolding aids that the mobile PDA of the BWL system can play and offer in the bird-watching activities, (2) to investigate if the affective and cognitive learning could be possibly benefited from the mobility, portability, and individualization of the mobile PDA of the BWL system.