Margie is an 11-year-old girl living in the year 2155 who receives individualized education at home. She struggles with geography, consistently scoring poorly, and strongly dislikes the daily routine dictated by her computerized teacher. Her introduction to a centuries-old printed book sparks her curiosity about how children lived and learned in communal schoolhouses. Feeling alienated by her technological environment, she deeply misses human connection and socialization.

Tommy is a 13-year-old boy who discovers a physical book about historical schools and shares it with Margie. He acts with superiority and occasional condescension toward his younger friend, frequently calling her ignorant about historical facts. Like Margie, he receives his education through an automated home system and lacks a traditional peer group. He shares his discovery primarily out of an unspoken eagerness for companionship despite his dismissive exterior.

The Mechanical Teacher is a large computer system installed in Margie's home, responsible for her daily, individualized education. It calculates grades instantly, delivers customized lessons via an illuminated screen, and requires homework to be submitted in punch code through a designated slot. It lacks human warmth or adaptability, strictly adhering to its quantitative programming regardless of the student's emotional state. The machine functions as the primary supervisor in Margie's daily life, enforcing a rigid and isolating routine.

Mrs. Jones is Margie's mother, who strictly enforces the automated, individualized educational model of the 22nd century. She maintains high expectations for her daughter's academic performance, expressing sorrow rather than comfort when Margie fails geography. She does not participate directly in Margie's daily learning, deferring entirely to the instructional machine. When the computer malfunctions, she promptly calls for technical support rather than adjusting the lessons herself.

The County Inspector is a maintenance worker described as a round, red-faced man who carries a physical box of tools, dials, and wires. He is responsible for repairing and adjusting the automated educational machines, specifically resetting Margie's computer to a ten-year-old level after a malfunction. He shows a rare display of empathy toward Margie's academic struggles, offering her an apple and a pat on the head. His brief visit provides the only emotional warmth Margie experiences during her school day.