Who could have imagined these results?
I witnessed this in my own household. My ex-gf had 2 kids by birth and 2 more that were adopted because her sister is an addict. Her idea of raising those kids through school was to wait until she saw bad grades from her eldest and then go to the school to blame the teacher. Mine was to actually sit with them and force them to do their assignments and study, which was especially helpful for the eldest adopted child, who was dyslexic. I grew up in a two parent, college graduate household. She grew up in a single parent household. Our differences in parenting style (we were living together for 7 years) had something to do with our breakup. I was demanding where it benefitted the kids and their future. She was demanding when it benefitted her (getting out of doing things around the house by making them do it).
Her eldest son is gifted and motivated and will probably do just fine. The others? Her eldest daughter is an excuse machine and the other one is just behind because of her dyslexia. Those kids have a ton of potential, they just need attention to reach it.