CNN.com:

gum-chewing students had a 3 percent increase in their standardized math test scores compared with those who did not chew gum. Also, the students who chewed gum had better final grades compared with the non-chompers.

He also reports that teachers anecdotally found that students who chewed gum required fewer breaks, paid better attention and stayed quiet longer than those who did not.

...

Another study adds to a growing body of evidence centering on chewing gum satiety and cravings. Investigators at Louisiana State University took 115 people who regularly chewed gum and fed them lunch. They measured their cravings before and after lunch. They found that those subjects, who chewed gum three times hourly after lunch, ate fewer high-calorie snacks. The chewers also reported decreased feelings of hunger and cravings for sweet foods.

...

The American Dental Association says on its Web site that "chewing sugarless gum for 20 minutes following meals can help prevent tooth decay" and recommends looking for gum with its ADA-approved seal. The saliva produced in the mouth by the physical act of chewing can wash away acids and bacteria, thereby protecting teeth.

Besides beating tooth decay, independent research finds that gum can aid in reducing the symptoms of acid reflux disease. The saliva flow can lead to an antacid effect in the stomach.

I knew I was right to love gum.