Casting populated List<BaseClass> to List<ChildClass>

I have a List<BaseClass> with members in it. I would like to cast the list (and all its members specifically) to a type List<ChildClass>, where ChildClass inherits BaseClass. I know I can get the same result through a foreach:

List<ChildClass> ChildClassList = new List<ChildClass>();
foreach( var item in BaseClassList )
{
    ChildClassList.Add( item as ChildClass );
}

But is there a neater way of doing this? Note - this is done on the WP7 platform.