This design experiment aimed to answer the question of how to mediate the practices of authentic science inquiries in primary education. An instructional approach based on activity theory was designed and carried out with multi-age students in a small village school. An open-ended learning task was offered to the older students. Their task was to design and implement instruction about the Ice Age to their younger fellows. The objective was collaborative learning among students, the teacher, and outside domain experts. Mobile phones and GPS technologies were applied as the main technological mediators in the learning process. Technology provided an opportunity to expand the learning environment outside the classroom, including the natural environment. Empirically, the goal was to answer the following questions: What kind of learning project emerged? How did the students' knowledge develop? What kinds of science learning processes, activities, and practices were represented? Multiple and parallel data were collected to achieve this aim. The data analysis revealed that the learning project both challenged the students to develop explanations for the phenomena and generated high quality conceptual and physical models in question. During the learning project, the roles of the community members were shaped, mixed, and integrated. The teacher also repeatedly evaluated and adjusted her behavior. The confidence of the learners in their abilities raised the quality of their learning outcomes. The findings showed that this instructional approach can not only mediate the kind of authentic practices that scientists apply but also make learning more holistic than it has been. Thus, it can be concluded that nature of the task, the tool-integrated collaborative inquiries in the natural environment, and the multiage setting can make learning whole.