A Colorado teacher who posted notes from her third-grade class online and started a social media whirlwind under the hashtag #IWishMyTeacherKnew said Friday the assignment had been a revelation for her.

Kyle Schwartz, 26, asked the eight- and nine-year-olds at her Denver inner city school to write down something they wished she knew about them, partly as a writing exercise, and partly as a way for her to learn about her pupils.

Responses included "I don't have pencils at home to do my homework," and "I want to go to college," to one tear-jerker from a girl who said she had no friends to play with at recess.