For as long as the NFL Combine has been going on, players have been subject to the Wonderlic Test. The Wonderlic test is a 12-minute, 50-question examination that is designed to test the aptitude of prospective employees for learning and problem-solving. The test score is based on the number of correct questions given in the allotted time, with a score of 20 being an indicator of average intelligence.
In his book The Thinking Man's Guide To Football, Paul "Dr. Z." Zimmerman listed the average Wonderlic score of NFL players by position. Here's how they rank from highest average score to lowest.
Offensive tackle - 26
Center - 25
Quarterback - 24
Guard - 23
Tight End - 22
Safety - 19
Linebacker - 19
Cornerback - 18
Wide Receiver - 17
Fullback - 17
Running Back - 16
Now, that doesn't mean that a low Wonderlic score necessarily indicates that a player is going to fail at the NFL level. After all, Dan Marino only scored a 15 on his Wonderlic test, and I think that he turned out relatively okay.
In the history of the NFL Combine, only one person has ever scored a perfect 50 on the Wonderlic test. His name was Pat McInally, a punter from Harvard that was selected by the Cincinnati Bengals in the fifth round of the 1975 NFL Draft. He also had the distinction of being the first Harvard graduate to play in both a Pro Bowl and a Super Bowl, doing so with the Bengals in 1981.
McInally's greatest contribution to sports may have come off the field, however. . .in the mid-1980s, he came up with the concept for a line of sports action figures that he pitched to the Kenner toy company. In a very short time, the Starting Lineup series of action figures was known from coast to coast and border. So, even if he wasn't exactly a football superstar, McInally wound up putting his brain to pretty fine use off the field.
Another Harvard graduate, current Buffalo Bills quarterback Ryan Fitzpatrick, came close to acing the test when he scored a 48 back in 2005 (and did so in nine minutes). Former wide receiver Kevin Curtis (who has played for five different teams in his career) and current Cleveland Browns tight end Benjamin Watson also each scored 48 on the Wonderlic.
You can take a stab at the Wonderlic yourself, if you'd like. You can take a simulated test that gives you three minutes and 36 seconds to answer 15 questions. It's not exactly the same, but it might be as close as you're going to get to taking the test.