If you're referring to ScaleOut ASP.NET Session provider, you can disable session state for some of your app's pages (or make session state as read-only) via the @Page directive's EnableSessionState attribute.
Another option is to use a hybrid approach for storing app data in ScaleOut in-memory data grid when you can combine the use of ASP.NET sessions with fine-grain ScaleOut's NamedCache API calls for reading/writing app specific objects from/to the grid, instead of storing all of that data in session.
