This PhD thesis focuses on the development and experimentation of a tool to support collaborative learning, in small autonomous groups, during field trips. To this end, we have developed SPART, a device for augmenting flat surfaces, such as maps or images, which can be used with standard smartphones or tablets. It provides a large workspace and intuitive interaction affordances similar to those offered by interactive tabletops. The device has been tested during a classroom activity, a field-trip and a science fare.This thesis also offers more theoretical contributions such as a definition and a conceptual framework, to better understand the elements and mechanisms inherent to collaborative learning. The PAC conceptual framework was built to be compatible with other scientific work, with the aim of becoming a collaborative artifact for the CSCL (Computer Supported Collaborative Learning) community. We also propose a meta-analysis of existing functionalities and their impacts on the different elements of collaboration to facilitate the design of collaborative software.