He prefers to choose easy work in class, and she's been making him do harder things. She believes he's afraid to make mistakes, that he has a self-confidence problem academically (he also hates to ask for help).
Could he be a perfectionist? These would be typical signs. DS5 definitely has problems with perfectionism. Things are pretty ok right now, but I am sure it will show up again.
I suggest reading Freeing Our Families from Perfectionism by Thomas Greenspon.
IQ test down the line may be a helpful too, but it's probably not necessary right now. It would be nice to know what to expect though.