Green will take his finals at Nebraska this week and then leave the school.
"It was a very difficult decision for him," Tony Green, Aaron's father, told HuskerOnline.com. "He's very tight with his brother (Andrew Green) which made this even more difficult. It's also been difficult on me and his mother. We really wanted him to stay, but in the end he had to make his own decision. It's not mine to make. He's got to be happy. It just wasn't meant to be for him and he's got to make his own decision."
"Coach (Pelini) didn't want him to leave and I didn't want him to leave. Towards the end though (Pelini) was pretty understanding of his decision."
Green rushed for 130 yards on 25 carries as a freshman while serving as a backup to Rex Burkhead. He was expected to take on a bigger role in 2012.
Green's father says his son is looking at Oklahoma, Baylor, Texas Tech, TCU and Houston as potential transfer options.