PLANO, Texas — Two years of college football, two years of being chosen the best receiver in the country. There wasn’t much left for Texas Tech’s Michael Crabtree to accomplish.

So now he’s eager to see how he’ll do in the NFL.

Crabtree said Tuesday he’s giving up his final two years of eligibility because he thinks he’s ready for pro football. The first challenge is finding out how high he’ll go in the draft.

“As far as I’ve seen, top 5. That’s what I’m striving for,” Crabtree said.

He joined a number of underclassmen Tuesday in announcing plans to leave school early for the draft. One notable exception was USC safety Taylor Mays, who will return to the Trojans for his senior season.

Tall, strong and fast enough, Crabtree averaged 120.3 yards and 1.6 touchdowns per game in college, extraordinarily high numbers even in coach Mike Leach’s video game-esque offense.

His career totals of 231 catches for 3,127 yards and 41 touchdowns would be remarkable over three or four years. Compiled over only two years, it’s no wonder he was an All-American both seasons and was a two-time winner of the Biletnikoff Award as the nation’s top receiver. He was fifth in voting for the Heisman Trophy this past season.

“I feel like the next level will be a big challenge for me and I’m looking forward to it,” Crabtree said.

Texas Tech defensive end Brandon Williams also announced Tuesday that he’s entering the draft. The reigning Big 12 sack leader is projected to be a third-round pick, but that was good enough for him.

“A lot of the coaches wanted me to come back, but I talked to my parents and we decided it was time to go,” Williams said.

• Ball State quarterback Nate Davis also decided to give up his senior season to enter the NFL draft.

Cardinals coach Stan Parrish made the announcement Tuesday in a news conference at the school.

Davis, a junior, led Ball State to a 12-0 start this past season, during which the Cardinals were ranked as high as 12th. The Cardinals lost to Buffalo in the Mid-American Conference championship game, then to Tulsa in the GMAC Bowl.

“I know what I’m about to do won’t be easy,” Davis said in a news release. “But it’s what my heart and head want to do at this time. It’s the right thing for me and my family at this time.”

Davis threw for 26 touchdowns and only eight interceptions this season and his quarterback rating was 13th in the nation.

• All-American defensive end Aaron Maybin will skip his final two seasons at Penn State and declare for the NFL draft.

The 6-foot-4, 245-pound sophomore led the Big Ten with 12 sacks and finished with 49 tackles — 20 for losses — as the Nittany Lions went 11-1 before losing 38-24 to Southern California in the Rose Bowl.

Maybin will be one of the top defensive ends available and is a likely first-round pick.

• Wide receiver Jeremy Childs will enter the NFL draft, leaving Boise State after his junior year and as the school’s No. 2 all-time pass catcher.

Boise State coach Chris Petersen made the announcement Tuesday. Childs was the Broncos’ leading receiver last season, catching 72 passes for 802 yards and seven touchdowns. He was a first-team all-Western Athletic Conference selection for the second consecutive season.

Childs finished his Boise State career with 168 catches for 1,999 yards and 17 TDs.

• Cornerback Asher Allen has joined the list of players leaving Georgia early to enter the NFL draft.

Junior quarterback Matthew Stafford and redshirt sophomore running back Knowshon Moreno announced last week they were entering the draft. Both are considered first-round picks.

Allen said Tuesday he finally made what he called a “family decision” to pass up his senior season at Georgia. Thursday is the last day underclassmen can declare for the draft.

• Meanwhile, Mays, an All-American safety, has decided to return to Southern California for his senior season rather than turn pro.

“There are a lot more things I want to accomplish as a player, a student and a person, things that I’ve dreamed about for a long time and that are big goals to me,” Mays said in a statement issued by the school Tuesday. “Returning to USC will help me be the best player I can be and put me in the best position possible for the next level.”

Mays, a three-year starter, was one of three finalists for the Thorpe Award as the country’s top defensive back. Malcolm Jenkins of Ohio State won the award.

“We’re obviously delighted to learn of Taylor’s decision,” USC coach Pete Carroll said. “He’s one of the most gifted safeties to ever play at USC and he wants to come back and do it one more time.”