You could try Early Birdies, esp if you apply now. Nurseries here are in short supply and have long (years) waiting lists, but Early Birdies seems to take in children at shorter notice and I've heard good things about it. Otherwise maybe a series of turnen/ play-gym classes each morning eg http://www.tvr1898.de/ . Or 1234Eckstein used to offer childcare in the summer hols, and they do little gym stuff otherwise. Have fun!
I don't live in Germany, but will be there for the summer and would like my daughter to have some activity in the morning and also learn german. We'll be in Cologne. Does anyone know any nurseries that are open in the summer? Thanks