Entity Framework - Load only Selected properties

No navigation properties are not loaded immediately. They are loaded either explicitly if you use Include method or lazily when you access them for the first time (that is also reason why you see them in debugger = access through debugger caused lazy loading).

You can load only selected properties - it is called projection. The limitation is that you cannot load Student entity with subset of properties. You need either new class or anonymous type:

var query = context.Students.Select(x => new 
                {
                   x.UserName,
                   x.Address 
                });