The last of the 12 jurors and four alternates were chosen in the second day of selection for the trial, scheduled to begin with opening statements Monday, The (State College) Centre Daily Times reported. Nine of the jurors were selected Tuesday.
The newspaper said 12 people were excused from the pool of 40, mostly for financial hardship reasons.
The Centre Daily Times said Sandusky joked with pool reporters covering the jury selection during a break in the process.
Earlier, ABC News reported Sandusky allegedly wrote love letters to boys he is accused of sexually assaulting.
The intimate letters to one accuser known as Victim 4 will be read into testimony after the trial begins, ABC reported, citing sources close to the case. Eight alleged victims who say they received similar letters from Sandusky are to testify against him, the network said.
ABC News said sources described the letters as "creepy" and said one was a story written in the third person.
Victim 4, now 28, is expected to be the first witness to testify against Sandusky, 68, charged with 52 counts of sexually abusing 10 boys in 15 years.
Some of the alleged assaults occurred on the Penn State campus. He allegedly met the boys through the Second Mile children's charity he founded.
If found guilty, the penalties against Sandusky could result effectively in a life prison sentence.