Since World War II, parts of the castle have been used by various educational establishments: firstly, by the Newcastle upon Tyne Church High School; then, from 1945 to 1977, as Alnwick College of Education, a teacher training college; and, since 1981, by St. Cloud State University of Minnesota as a branch campus forming part of their International Study Programme.
Siden anden verdenskrig er slottet blev brugt af forskellige uddannelsesinstitutioner; først af Newcastle upon Tyne Church High School; herefter som Alnwick College of Education fra 1945 til 1977, som læreruddannelses college; og siden 1981 af St. Cloud State University fra Minnesota som en campus som en del af deres internationale studieprogram.