The Williamsport, Pennsylvania, native has two years of eligibility remaining.
"They're looking for somebody to look to, they're looking for a standard, and I feel like I have to be the standard..."
In partnership with Soles4Souls, 12 Penn State football student-athletes will take a service trip to Guatemala in May.
Washington's effectiveness in the air and after the catch makes him an enticing NFL draft prospect.
Mitchell is the second cornerback to join the class.
Cottrell has committed to Penn State after earning a preferred walk-on offer in January.