// pseudo: if month(entered) greater than or equal to 7, return year(entered)
// else return year(entered)-1 (for school year conversion)
// returns distinct list of "school years"
 
var criteria = Session.CreateCriteria<MyEntity>();
var convertToSchoolYearProjection = 
Projections.Conditional(
 Restrictions.Ge(
  Projections.SqlFunction("month", 
    NHibernateUtil.Int32,