考查细节理解。根据第一段第二句“When students in her class started calling Prisilla a boy, she felt ashamed, often crying and losing focus in school”可知，Prisilla在学校不开心是因为她被同学嘲笑，故选C项。

10．What made Grimm have her own hair cut?

A．Praise from her students.

B．Devotion to her students.

C．Request of Prisilla's mother.

D．Suggestion from the hairstylist.

解析：B　考查推理判断。根据第三段的内容，尤其是“Grimm thought about Prisilla... she had an idea: Cut off her hair”可知，Prisilla因为是短头发而被同学嘲笑，为了安慰Prisilla, Grimm老师决定把自己的头发剪短。由此可推知，Grimm老师出于对学生的关爱才剪短了头发，故选B项。