Barcelona has a wide range of theaters and plays for children: storytelling, dance, music ... the billboard is available to check the plays view the offer of the moment.
It is very interesting for children's the cycle "Petit Liceu" organized by the Liceu de Barcelona. These small operas adapted for children of all ages (see recommended ages for each performance). The play lasts about 1 hour. Representations can be at the Liceu in Barcelona (which is a good opportunity to also visit the famous theater with splendid décor) or Cornellà Auditorium (refer to dates selected works and the place of representation). Prices are very affordable, about 12 €, but you can buy tickets for at least 3 family works and the price is lower (10% off plus other benefits).