Most likely Barney is the main character. There may also be teachers, classmates, and perhaps a school principal.
The 'Barney Goes to School Story' would probably have Barney as the protagonist. Alongside him, there would be a diverse group of classmates with different personalities. The teachers play a crucial role as they guide Barney through his school day. There could be a kind and helpful principal who oversees the school. Maybe there are also cafeteria workers who serve food during lunchtime and add to the overall school atmosphere.
In the story, Barney probably has a lot of new experiences at school. He might meet new friends, learn new things from teachers, and explore the school environment.
Obviously, Dora is a main character. There might be her parents who help her get ready for school.
In the 'bono goes to school story', Bono is the central character. However, his parents could also be considered main characters in a sense. They are the ones who send him to school, and their influence on his school - going attitude and behavior might be part of the story. Also, any special friends he makes at school, like a best friend who he shares all his school secrets with, would be among the main characters as they contribute to the plot and Bono's experiences at school.
Probably Franklin is the main character. And there might be his teachers and classmates as important characters too. His teachers would be involved in his learning process, and his classmates would be part of his social experience at school.
Froggy's classmates could also be main characters. In a school story, the interactions between Froggy and his classmates are usually important parts of the plot. They might study together, play together, and experience different things together, which makes them important characters in the Froggy Goes to School story.
David is surely an important character as the story is about him going to school.
Pepper is surely one of the main characters as the story is about Pepper going to school.
Well, Pippi is the central figure in the 'Pippi Goes to School Story'. Alongside her, there could be a friendly classmate who becomes Pippi's first friend in school. And there may be a headmaster or principal who has to deal with Pippi's unique personality and the situations she creates in the school, like when she does something unexpected during an assembly or in the classroom.
Well, Ottoline is surely one of the main characters as the story is about her going to school.
Perhaps some of Noddy's classmates could also be main characters. They would play a role in Noddy's school experiences, like sharing toys or helping each other with schoolwork.