This article describes how secondary education students from the state of São Paulo, Brazil, protested against the closure of ninety-four schools of public educational system. The movement named 'Do not close my school' was a combination of online protest, using Facebook pages, occupy-type protest, in which students occupied more than 200 schools, and demonstrations, which occurred in different cities of the state. It was a movement organized by the students, with no official support of school managers, and lasted more than two months. We analyse the activities involved in the 'Do not close my school' movement under a Cultural-Historical Activity Theory framework, and we discuss how the concept of collaborative agency is important for the development of such a protest. As data, we use the content of pages on Facebook from fifty-six groups related to the school occupation and 111 official pages, also on Facebook, from the schools. We performed a multimodal and network analysis of the data in order to understand how the movement developed which results were obtained by the students. Our findings suggest that by acting collaboratively students were able to reach satisfactory results from their protests. In addition, they expanded the activities in their groups on Facebook to other contexts, like organizing events in their schools or using them for other social movements.