Beck, a second-round pick, threw for 79 touchdowns and 11,021 yards at Brigham Young. He was the first quarterback selected by Miami in the first two rounds since Dan Marino in 1983.
Beck's agent, Justin Schulman, said his client agreed to the deal late Sunday, but declined to release its terms.
Ginn, an Ohio State receiver and Miami's first-round choice, remained unsigned. Ginn's agent did not return a phone message.
The Dolphins also signed two other players: center Drew Mormino, a sixth-round pick, who agreed to a four-year deal, and undrafted free agent Brian Soi, a 6-3, 315-pound defensive tackle.
Soi went on the active-non-football injury list.
Miami's other second-round pick, center Samson Satele, signed a four-year, $2.89 million contract on Thursday.
Rookies are scheduled to begin practice Tuesday and team training camp starts Saturday.