Why is it so important for you to make Finland as Scandinavia? When it's not.
What should be the difference between The Nordic countries and Scandinavia then?
If we include Finland then allot of History pages here should be changed, and then should we also include the Baltic countries. 
Text books in Norway, Denmark and Sweden don't include Finland. Simple because Finland not are Scandinavia. 

You may probably find this link interesting. Comanche cph