22. How to Scare a Child 101
Apparently, they stopped doing the blood type comparisons in schools because it was too traumatizing to children. Too many were finding out they were adopted or only one of their parents was their real parents. That has to be traumatic for a child, though better for the truth to come out than to live a lie.

What is taught has to be careful, as this situation could have led to potential problems with this particular student. It seemed to have inspired them to pursue something in life, but doing it out of spite isn’t a great reason. Then again, negative emotions are a powerful motivator.