The main visual elements are the three members of the family. This cartoon is about the issue of children coming home from school and not wanting to talk to their parents about it.
The cartoonist thinks that kids should talk to their parents about their day and how school went. The evidence of this is that it shows the parents wanting to know what the kid did at school but he told them to just read his blog. This is an ironic cartoon because this cartoon is in a blog posting even though the parents are telling him to tell them what happened today.