Sussex Borough. Sussex Middle School will hold its annual senior breakfast, featuring a showing of this year's musical, Disney's Frozen, Jr., on Tuesday, March 24. Breakfast will be served from 8:45 to 9:45 a.m. in the Sussex Middle School cafeteria. RSVP by March 17 to (973) 875-4138. Leave a message with your name and the total number in your party.