In this study a teacher training program for Autism Spectrum Disorders (ASD), based on "structured teaching" (Mesibov et al., The TEACCH approach to autism spectrum disorders, 2006) was developed and evaluated within a Pre-Post design. In total, 10 teachers working with 10 students with ASD (mean age 10.0 years) in special education classrooms in Germany were involved in the training, The Pre-Post outcomes measured by teacher questionnaires indicated significant improvement on the Classroom Child Behavioral Symptom Scale as well as on the corresponding Classroom Teachers' Stress Reaction Scale. In addition, teachers implemented two structured teaching methods on average in their classrooms. These findings provide some first evidence for the clinical and social validity of the training program examined.