Studies in cell culture, animals and first clinical trials in adults as well provided evidence for efficacy of valproic acid and chloroquine in the treatment of glioblastoma. Due to this we hope children and adolescents suffering from GBM, DMG, AA, DIPG und GC will benefit from the treatment, too. As common for clinical trials, the treatment of the patients will be settled in a randomized manner to ensure impartiality of the investigators.