Historic Scotland's free entry weekend is 1st and 2nd April 2006.

http://www.historic-scotland.gov.uk/...rticleid=20739

and

http://www.historic-scotland.gov.uk/...reeweekend.htm

Go on, you know you want to visit a castle Besides, it's a huge saving. Normal adult entry to Stirling castle is £8.50 , multiply that up for a family and it's an expensive outing even if it is a great place.

Cheers,
Toddy