Many mobile learning projects aim to support new learning forms like situated learning in a real world environment. Situated and explorative learning should be active learning, engaging students in the environment. We tested four different tasks designs in two large field tests with the mExplorer system. Two kinds of engaging tasks were observed. Interactive tasks with high context integration led to knowledge about specific aspects of an environment. Creative tasks led to a familiarization with the environment. We also analyzed other projects with situated real world learning scenarios to see what types of tasks they were using. We found that instead of sup-porting active learning, many of these projects still focus on transmissive elements and do not use the full potential of situated and explorative learning. To optimize this, we propose four design recommendations for tasks and de-scribe the circumstances under which specific types of m-learning tasks should be used.