Positive effects of learner control decrease when learners do not perceive the control given to them, make suboptimal choices, or are cognitively overloaded by the amount of choice. This study proposes shared control (i.e., learners choose from a pre-selection of suitable tasks) over highly variable tasks to tackle these problems. Ninety-four students participated in a 2 x 2 factorial experiment with the factors control (system, shared) and variability of surface features (low, high). Results show superior effects on training performance, transfer test performance, and task involvement of shared control when learners can choose from pre-selected tasks with surface features that are different from the surface features of previous tasks.Key words: Cognitive load, learner control, surface features, system control, variability. Recent instructional theories advocate on-demand methods of instruction in which learners are given freedom to choose their own learning path (Bell & Kozlowski, 2002;Schnackenberg & Sullivan, 2000;Williams, 1996). In contrast to system-controlled instruction, learner-controlled instruction allows learners to make their own decisions on specific elements of instruction. These include, for example, the instructional components (e.g., learning tasks, information elements), the component characteristics (e.g., task contexts, modality of presented information), as well as task sequence and instructional pace. Instructional locus of control can be thought of as a continuum ranging from full system control to full learner control, involving several forms of shared control (Hannafin, 1984). Learner control is believed to positively influence learning and motivation (Kinzie & Sullivan, 1989;Ross, Morrison, & O'Dell, 1989;Schnackenberg & Sullivan, 2000;Williams, 1996). It permits learners to adapt particular characteristics of the learning material to their individual preferences and needs (Kinzie, 1990; Merrill, 1994), and has been theorized to be a useful alternative to the classical aptitude-treatment interaction approach in that learners can become system independent (Federico, 1980). Although the beneficial effects of learner control are supported from a theoretical perspective, empirical research shows both beneficial and detrimental effects on learning.These inconsistent results suggest that learner control can be either motivating or de-motivating (Katz & Assor, 2007). According to Skinner (1996), there is little consensus on the kinds of control that are beneficial or harmful for learning and on how these may interact with certain learner and situational characteristics. In any case, the unconditional use of learner control is not supported (Freitag & Sullivan, 1995; Lin & Hsieh, 2001;Skinner, 1996;Williams, 1996).Potential threats of learner control include, amongst others: (1) a lack of perception of control First, with regard to perception of control, some authors (Cordova & Lepper, 1996; Katz & Assor, 2007; Kinzie, 1990; Langer, 1975; Lepper, 1985;Taylor & Brown, 1988) argue that...