The 2013 Penn State football season has been a roller-coaster ride. The Nittany Lions opened with a close win over Syracuse in Christian Hackenberg’s first game. Penn State dominated Eastern Michigan the following week before losing to Central Florida in a heartbreaker.

The Nittany Lions shutout Kent State the following week before heading to Bloomington for an upset loss against Indiana. The game of the season, of course, was Saturday’s four-overtime shocker against Michigan.

With six games in the history books, Penn State is halfway through the season with a 4-2 record. It’s time for the Nittany Lion’s first half report card:

The Passing Game:

Christian Hackenberg has had his ups and downs, struggling on occasion but looking like the top quarterback recruit in his class most of the time. With a few exceptions, his decision making and football IQ have made him look more like a veteran than a true freshman.

Bill O’Brien clearly trusts Hackenberg, letting him throw the football 38 times a game. His numbers have reflected that trust, as the freshman has thrown for 1,672 yards with 11 touchdowns and six interceptions while completing 58.4 percent of his passes.

Some of the credit for Hackenberg’s play has to go to his receivers. Unsurprisingly, Allen Robinson has been stellar so far, catching 43 balls for 705 yards and five touchdowns.

Three other receivers have at least 13 receptions, including Brandon Felder and tight ends Jesse James and Kyle Carter. Bill Belton’s versatility has been on display, as he’s become the best receiver out of Penn State’s backfield, hauling in eight passes for 86 yards and two scores.

Grade — A: Despite some struggles from time to time, the passing game has been impressive this season. With 283.7 yards per game, the passing offense is the 28th best in the nation.

The Running Game:

Penn State has developed a three-headed monster at running back this year. Zach Zwinak leads the way with 92 carries for 393 yards and 8 touchdowns, while Belton has carried 70 times for 369 yards and three touchdowns. Perhaps the most impressive of the group, though, is Akeel Lynch, who is averaging 7.7 yards per carry with 270 yards and a score.

Don’t let the term “three-headed monster” fool you. The unit hasn’t been exceptional every game. In fact, the run game has been pretty boom-or-bust through the midway point of the season.

There was no rushing attack in the opener against Syracuse. The backs ran for 251 yards and five touchdowns against Eastern Michigan. Against UCF, the unit kept up the same pace, running for 193 yards and three touchdowns. Zwinak ran for three touchdowns against Kent State.

The run game was nonexistent against Indiana, a team that isn’t known for its ability to stop the run. The same can be said for Saturday’s game against Michigan, when Penn State passed well against a poor passing defense, but couldn’t run against a poor rushing defense.

Grade — B-: In short, the running game has been amazing at its best in four of the first half games, but terrible at its worst in the other two. With 157.2 yards per game, the rushing offense is the 75th best in the nation.

The Passing Defense:

Penn State’s secondary has been one of the low spots thus far. Nobody has expected young cornerbacks Jordan Lucas and Trevor Williams to be perfect, but they have really struggled at times in coverage.

The UCF game epitomizes the pass defense’s play in the first half. The offense did everything it could to lead Penn State to a win, but UCF quarterback Blake Bortles had his way with Lucas and Williams, and the Nittany Lions lost the game.

The safety play has been much better. Malcolm Willis and Adrian Amos have been much better than Lucas and Williams, with Amos even playing cornerback on occasion. Despite playing safety as a freshman, Amos was the team’s #1 cornerback last year.

Despite missing time with a hand injury, Ryan Keiser has been impressive at safety this season. Stephen Obeng-Agyapong has bounced back and forth between safety and linebacker, and has been outstanding in both spots.

Penn State’s pass rush has been solid, too. Deion Barnes hasn’t racked a ton of sacks, but he is facing a lot of double teams and opening things up for everyone else on the defensive line. Barnes’ bookend, C.J. Olaniyan, has had a breakout year, with his best game coming last week against Michigan.

Grade — C-: The passing defense has shown signs of improvement, but there’s still a long way to go.

The Rushing Defense:

Contrary to the secondary, the front seven has stepped up big time this season. The rushing defense has been up and down — against Syracuse, Eastern Michigan, and Kent State, the Nittany Lions allowed 71, 61, and 56 yards, respectively.

UCF running back Storm Johnson was one of several Knights to shred Penn State, as the team rushed for 219 yards. Against Indiana, the Hoosiers ran all over the Nittany Lion’s defense for 150 yards on the ground.

Michigan put up 149 yards on the ground, but 121 of them came from quarterback Devin Gardner. The Wolverines’ featured running back, Fitzgerald Toussaint, ran for just 27 yards on 27 attempts.

DaQuan Jones disappeared for a few games, but has been generally outstanding at defensive tackle. The linebacker unit has lived up to the Linebacker U name, led by Mike Hull and Glenn Carson. Nyeem Wartman has rounded out the unit, with Obeng-Agyapong playing well when defensive coordinator John Butler slides him up into the box.

Grade — B: The rushing defense has stepped up when needed…for the most part.

Special teams:

Two words: Sam Ficken. He hit a career long 54-yard field goal against Kent State, and is 6-for-6 on kicks within 40 yards this season. The memories of his nightmare game against Virginia are a thing of the past. Ficken is a trustworthy kicker and has been one of the best in college football so far this season.

In the punting game, Alex Butterworth certainly hasn’t been great, but he hasn’t been horrible, either. Butterworth shows flashes, blasting monster punts from time to time, but he’s been generally mediocre.

As for the kick return and punt return teams, there haven’t been any touchdowns, but the units have been good. The kickoff and punt teams haven’t allowed any big plays.

Grade — B+: If Ficken keeps it up, he could actually earn himself some awards this year. Imagine that.