Wonder Girls' Yenny surprised everyone when she revealed that she was first in her class and among the top 10 in her entire school on 'Happy Together 3'.

On the show, the five 'brainy' guests gave their own secrets for studying well. Yenny's secret was, "Make a friend who takes good notes." She revealed that her secret was not to increase her smarts, but to get good grades on tests.

She revealed, "In a person's life, balance is important. It's not like you can only keep studying. That's hard. In my case, I was also in a dance club and did other activities. So when there was about two weeks left until the exam period, I'd pick out a friend who I could immediately tell takes good notes in class. I was usually good friends with them, and before the test, you borrow their notes. You then copy everything. But you can't copy just one person's notes, you have to get notes from at least two people. You can't trust just one person."

Her second tip was, "Study out loud." She explained, "Usually, people study just with their eyes. But if you do that, your concentration drops. If you study out loud, not only is your mouth moving, but you hear the information as you're reading. So it stays longer in your head." She gave an example of how she studied by saying, "I really liked imitating my teachers. So if my Korean teacher used a dialect, I would do the same when I studied."

She added, "When you do group study, you also have to make sure the people are all good at different things."

Will you be taking her advice?