Theory:

     “But my mother says a teacher has to be adjusted to fit the mind of each boy and girl it teaches and that each kid has to be taught differently.”
 
     “Just the same they didn’t do it that way then. If you don’t like it, you don’t have to read the book.”
 
     “I didn’t say I didn’t like it,” Margie said quickly. She wanted to read about those funny schools. They weren’t even half finished when Margie's mother called, “Margie! School!”
 
     Margie looked up. “Not yet, Mamma.”
 
     “Now!” said Mrs Jones. “And it’s probably time for Tommy, too.”
 
     Margie said to Tommy, “Can I read the book some more with you after school?”
Explanation:
  
Margie tells about the machine teacher. Margie mother said that the machine had to modulate to the level of individual boy or girl study form it. Each child had to be taught separately depending on their ability.
 
Tommy responded that in the past, they did not do it that way. He got annoyed at Margie and said that she need not read the book anymore.
 
Margie was curious about the book. She liked to know more about those schools. She thought that they were fun. Margie and Tommy didn't read even read half of the book when her mother called her as it was time for her to take part in her virtual school. Margie’s school was in the next room.
 
She did not want to go to that school yet.
 
Margie’s mother said to Tommy that it was time for him to go to school as well.
 
Margie was so immersed in reading the book that she requested if Tommy could read the book with her after the school gets over.
Reference:
State Council of Educational Research and Training (2018). Term-1 English Standard-9. The fun they had - Isaac Asimov (pp. 150-153). Published by the Tamil Nadu Textbook and Educational Services Corporation.