"I would say they're trailing just because I don't know much about them and I haven't visited," Jackson said.
Jackson, a former Duke verbal commitment, said that Illinois, Iowa and Pittsburgh are the schools he's now considering. His favorite, Michigan State, is supposed to let the Columbus Marion-Franklin High product know on Tuesday if he'll get an offer from the Spartans.
"They're my number one school," the 6-foot-3, 260-pound Jackson of the Spartans. "I'm either going to visit there or Iowa this weekend. I won't be visiting Michigan State without an offer, though."
Jackson said he really enjoyed his visits to Illinois and Pittsburgh. He said they're standing out among the schools that have offered a scholarship.
Scout.com lists Jackson as a three-star recruit on its five-star scale. The service lists him as the 66th best DT nationally in the 2012 class.
Jackson's Iowa offer came while Chicago-area DT Jaleel Johnson was officially visiting the school. At the same time, another Hawkeye target at the position, Aaron Curry from Texas, was in Lincoln on his Nebraska official.
Johnson, who verballed to Iowa in the summer, still is deciding whether or not he will visit Michigan State this coming weekend. Curry is expected to choose between the Hawkeyes and Nebraska after in-home meetings with coaches from those schools later this week.