The riba Architecture Gallery is taking part in Gallery Week 1999 by staging its first Open Saturday - a day of events for children and families. To take place on Saturday 17th July from 11am to 4pm,it will include explore! - where a range of activity guides to 66 Portland Place will be available throughout the day for children to investigate the building's 1930s interior. The Gallery will put its carvings and sculptures to good use with a competition to spot lions around the building. Other events include a cartooning session with the aj's Louis Hellman and a diy Architecture Workshop with Hackney Building Exploratory which will give children the chance to design their own houses.