Day 15 and Day 16
For these two days, count how many times you gossip, someone gossips to you or you overhear someone gossiping about you. Try to stop yourself from gossiping by saying something like "I don't really want to gossip." You can send in your observations of gossip to email@example.com or keep it private.
Notice when you do Lashon Hara, literally meaning the evil tongue, or when you gossip. Gossiping is idle talk or rumor, especially about the personal or private affairs of others: the endless gossip about Hollywood stars. It is important to try to not gossip because you can inadvertently hurt others. People do gossip however, but try to be the person who says "we shouldn't gossip." Lashon hara is essentially spreading judgments that you make about people to other people. They then make that judgment too, even if it isn't true.
Check out this book about lashon hara, Words That Hurt, Words That Heal By Rabbi Joseph Telushkin