The study examines the use of weblogs in teacher education internships and its impact on student stress levels, self-efficacy, and reflective abilities. One hundred and seventy-six student teachers were randomly assigned to five groups. Four groups used weblogs (a) with emotion-focused or with problem-focused writing assignments in combination (b) with or without peer feedback during a 4-week teaching practice on a daily basis. The control group wrote a final reflection paper instead of blogging. Multilevel linear modeling of longitudinal questionnaire data shows that students with problem-focused weblog writing assignments show a stronger development of self-efficacy during the internship than the other groups, especially when combined with peer feedback on blog postings. Groups do not differ with regard to stress levels and ability for reflection.