I think a child/young adolescent tripping another classmate, and an adult forcibly shaking a baby to cause the injuries this boy sustained are completely different, and criminal!
Both were bursts of anger. The kid that tripped me did it because I was making fun of him as he was described in a newspaper article (went on a cross atlantic sailing trip with his dad on their boat). I was making fun of the title they gave him in the article.
IOW, like the woman who shook the baby, he was angry and lashed out.