The article reviews the use of Web 2.0 environment in teacher education, emphasizing the constructivist social pedagogy approach. Pedagogical abilities of Web 2.0 tools are discussed, demonstrating their applications in teaching various subjects, especially to assist collaborative and creative learner-oriented teaching. Contributions of these tools to teaching-learning are described in three collaborative environments-based courses. The tools included: forums, collaborative synchronous lectures, Wiki environment, a closed Facebook group, blog writing, collaborative documents writing, using smartphones in lessons and location-based activities, class YouTube channel for student-teachers' clips and debates, structuring collaborative knowledge and online anonymous peer assessment regarding discussion on digital citizenship, group data collection through surveys etc. Intertwining various environments to assist course teaching increased student-teachers' awareness of effective exploitation of these environments for teaching objectives. Pedagogical considerations for choice of tools, environments, and applications are discussed. Conclusions relate to the contributions of ICT, contents, and pedagogy integration to teacher education.