Berlin is great place for kids. Children are welcome almost everywhere and there are facilities throughout the city that are setup to support and accommodate them.
There are plenty of activities, open spaces and playgrounds to keep them entertained. For example, each neighbourhood has a local pool well-equipped for children. There are also a few indoor amusement parks around town such as FEZ (http://www.fez-berlin.de) and Bim & Boom (http://www.bim-boom.de). Many of the museums have special exhibits and programs to keep young minds engaged – especially MachMit (http://www.machmitmuseum.de) in Prenzlauer Berg which is specifically designed for children. Here it is all about hands-on fun. The is an aquarium and there are two zoos – the well-known Berlin Zoo with the famous polar bear Knut located in the East and the other, Tierpark, a free-range style zoo with more space for animals. More information on all three can be found at http://www.zoo-berlin.de/en.html. Although the website is in German it is easy to access information on opening hours, directions and activities.
Taking kids out in the evening is common and supported. If you take your children along for dinner, many restaurants will have children’s menus and colouring gear, although not necessarily highchairs.
From an educational standpoint, the daycares and educational facilities are of a high standard. Children are encouraged to express themselves and much of the school curriculum reflects the Steiner Waldorf approach to education and child development (http://en.wikipedia.org/wiki/Waldorf_education). Children are encouraged to explore nature and their surroundings, expand their imagination and be active. The idea of marketing to children, as seen in America, Britain or Australia is unheard of in Germany.
Berlin is a very safe environment for children. Within the first few years of primary school, children walk themselves to and from school. Culturally, Germans encourage child interaction and even the older generations expect the young to participate in conversations, rather than the old idea of kids being seen and not heard.