Children's books for high school

Ms. Takase had taught for ten years in a girls' high school, and used native English written children's picture books as a main source for her students learning. The students were allowed reading time in the library, in which they could choose any book they liked and read it for enjoyment. There were no tests and there was no requirement to translate. After one year, the students' scores on regular English tests rose significantly and the average scores were higher than students who had not taken Ms. Takase's reading course. This convinced the high school, over time, to buy and stock its school library with over three thousand English children's picture books!