The collaboration and cross-border communication of 14–16-year-old students from Sweden and Denmark working with various science assignments using ICT was followed in an action-influenced project. The students collaborated in a complex learning context, including searching for information, planning, executing, and reporting experiments, posing questions, collecting facts, and communicating, using the Internet, shared documents and presentations, Blog, Skype, and Adobe Connect. The asynchronousICT communication tools used in the project enabled the teachers to include information and instructions for the students in the documents as well as following the students work online. The synchronous communication tools were importantfor the students to get to know each other and make friends.Most of the student groupswere successful in using the ICTs provided, in executing the experiments, communicating, and sharing information. Generally the students appreciated the possibility ofworking with fellow students from another country; they showed good ability to work autonomously, collaborate, and communicate about science issues. The ICT tool that were most popular among the students were Google docs and Skype.The complex learning situations created within the project enabled the students to interact regardless of physical borders and to trainin important key competencessuch as using scientific methods, developing digital skills, and communicating in the mother tongue as well as in foreign languages.