The title is a parody of the legal concept and American constitutional right of all accused persons to trial by jury.
The teacher says the test is comprised of 15 questions. First five are worth 9pts each (45 pts), 8 pts each for next 5 (40pts) and 3 pts for the last 5 (15). When Hilda goes to talk to him, he says the first ( questions were worth 40 pts which is the middle 5 questions.
Opening Credits Outfit: Sabrina changes into an equestrian outfit with riding boots and says "We'll be back in," scrapes foot twice, "minutes."