There was plenty of moving and shaking in the first half, with Kyle Busch emerging as the class of the field. Jill Erwin hands out grades for the first 18 races (min. 10 starts):

Kyle Busch GRADE: A+
The easiest grade to give. He's won one-third of this season's races and finished in the top five in nearly two-thirds. A stupendous season.

Carl Edwards GRADE: A
Were it not for a 100-point penalty, Edwards would be second in points. He has three victories and three more runner-up finishes.

Dale Earnhardt Jr. GRADE: A
Junior has lived up to the hype with Hendrick, breaking his winless streak and finishing in the top five in 8 of 18 races.

Jeff Burton GRADE: A
Daytona (July 5) was his first non-top-15 finish in 2008, and Burton has regained the consistency that has been his hallmark.

Jimmie Johnson GRADE: A
Consistency could be his middle name. A late wreck ruined his trip to Daytona (July 5), but he's finishing races and safely in contention.

Jeff Gordon GRADE: A
The positive? Seven top-five finishes. The negative? Three DNFs and zero wins. Still, he's solidly in the Chase and a danger to win.

Travis Kvapil GRADE: A
Kvapil is in the top 20 despite no sponsorship and limited Cup experience. Yates Racing is getting its money's worth.

David Gilliland GRADE: A
See Kvapil. Gilliland has limited funding from sponsors but has managed to largely keep his nose clean.

Brian Vickers GRADE: A
Vickers is 16th in the points, and he has three top-five finishes to show for his second season with Red Bull.

Matt Kenseth GRADE: B+
Kenseth is easily the most improved from the start. He was 22nd after Richmond and 13th last week. Now he's ninth.

Mark Martin GRADE: B+
The old man's still got it, finishing in the top 10 in half of his races despite a lack of continuity, thanks to his part-time schedule.

Denny Hamlin GRADE: B+
He's run well, but he's not getting the finishes. That's a refrain for most drivers, but Hamlin's living it.

Kasey Kahne GRADE: B+
Kahne's hot stretch has cooled off, but he's still in the top 10. Kahne has more wins and poles combined (four) than anyone but Kyle Busch.

David Ragan GRADE: B+
One of the forgotten Roush Fenway drivers is quietly putting together a strong season. He's in striking distance of his first Chase.

Clint Bowyer GRADE: B
It's not a fluke. Bowyer has followed up last season's breakout with solid runs. He's been running at the end of all 18 starts.

Greg Biffle GRADE: B
Biffle lost three spots in the points at Daytona, but he's been a solid contender this year. Plus, he's got two poles.

Tony Stewart GRADE: B
The DNFs (three of them) aren't his style, and Stewart's had a pretty crazy season. But this is time for his patented summer run.

Kevin Harvick GRADE: B
He's 13th in the standings, but Harvick will be the first to tell you he wishes he had more to show for this season. Don't count him out yet.

Martin Truex Jr. GRADE: B
The banner driver for DEI, Truex hasn't yet found his stroke. He's been solid, if unspectacular, but he'll need more for the Chase.

Ryan Newman GRADE: B
The Daytona 500 winner is talking about leaving Penske if his cars don't get better, and it's hard to argue. He expects more than two top-fives in 18 starts.

Juan Pablo Montoya GRADE: B
Montoya obviously has talent, but his patience (i.e. his penchant for retaliation) leaves much to be desired. He's got to grow up.

Kurt Busch GRADE: C
He has nearly as many DNFs (three) as he does top-10 finishes (four). Not really what the 2004 series champ was looking for.

Bobby Labonte GRADE: C
He's coming off back-to-back top-15 finishes for the first time this season, but he's too up and down to be a serious threat.

Paul Menard GRADE: C
His first pole and second top-15 finish aren't enough to make Menard more than an afterthought on any given week.

David Reutimann GRADE: C
Reutimann has had to change cars, crews and mindsets. He's had some good runs in the 44, but he needs to show more.

Robby Gordon GRADE: C
A sixth-place finish at Daytona was a continuation of a good run there in February. He just needs to figure out the non-restrictor-plate ovals.

Elliott Sadler GRADE: C
Sadler's a good guy, but he just isn't in the same class as a driver with his teammate Kahne. And his results show it.

Patrick Carpentier GRADE: C
See Sadler. Carpentier gets points for showing up every week and racing his way into the field; now he needs to work on finishes.

Jamie McMurray GRADE: D+
McMurray has been caught up in some accidents, like at Daytona (July 5), but he's also not competing at the same level as his teammates.

Dave Blaney GRADE: D+
Blaney is still recovering from a tough start to the season, but finishing 30th or worse in nearly half the races won't help.

Regan Smith GRADE: D
Smith is just 24, and he's learning as he goes. But he has to pick up the pace soon if he wants to be more than an also-ran.

Michael Waltrip GRADE: D
He was on the verge of back-to-back top-10s at Daytona (July 5) before the final wreck, which dropped him to 27th.

Scott Riggs GRADE: D
No reason for this team to be running this poorly with Hendrick assistance and a capable guy like Riggs. Something's got to change.

Casey Mears GRADE: D
Mears isn't a terrible driver, but he's not as good as the ride he's in. He's faced adversity through changes, but he hasn't conquered it anywhere he's gone.

Reed Sorenson GRADE: D
Sorenson is a non-factor in nearly every race, which might be worse to a driver's career than if he had severe highs and lows.

Sam Hornish Jr. GRADE: D
Hornish came into the season with a five-race cushion. He couldn't keep it up, and now he's on the verge of falling back out of the top 35 in owner points.

Joe Nemechek GRADE: D
One pole is good. Three DNQs and two top-20s aren't. Nemechek is no longer a threat.

A.J. Allmendinger GRADE: D
He's well behind his teammate, Vickers, thanks to some mistakes and a hiatus from the car. Allmendinger has to be more consistent.

Michael McDowell GRADE: D
A big splash into Cup racing has been followed by a dribble in the results column.

J.J. Yeley GRADE: F
Yeley's is a satellite team of Joe Gibbs Racing. Yet, he's not even in the same solar system as JGR.

Dario Franchitti GRADE: I
Franchitti gets an incomplete, seeing as to how he doesn't have a ride. But he wouldn't have been much higher had his season continued.