You all are right... they LOVE to share. I do several things to let them do it. After we do our lunch count during morning meeting my Handy Helper(one per day) has to run this to the office. While they are gone I ask "who has something exciting to share?" They raise hands and I let them speak... this is every day. Usually, about 3 or 4 get to speak before Handy Helper returns. I also let kiddos bring in things that pertain to particular units we are doing. That only happens every once in awhile so it really doesn't take much time.
One of my favorite things to do is the Mystery Box (like a PP)! I have a little box. It's actually one of those metal photo boxes with a see through front pocket. I have a card that says MYSTERY BOX ?. The box actually latches like one of those old timey metal lunch boxes. I think I got it a Dollar Tree or Dollar General a few years ago, but I've seen them lately.
I use a ring binder and whole punch index cards in the corner (how many are in my class). They use these to write their clues. I put the box, the index card clue keeper, and the directions in this vinyl bag that clasps shut. We rotate through the class... everyone gets several turns. They LOVE it. Here's my letter that I print off, put on construction paper and laminate to keep it good all year.