1. Hop like a frog. Yep, I'm THAT photographer. I will do what needs to be done. This one is definitely hit or miss and only works for a certain age (2 year olds seem to love this), but when it works, the kids think it is hilarious. I hope like a frog and say "ribbit" while trying to get a clear picture before the smile fades. Mom and Dad usually smile too, which is an added bonus.
2. Speed boat noises. For really little ones, this works. I try as many sounds as needed for the really little ones. Sometimes saying "AHHHHHH!" really loud works too.
3. Who has... When they start getting a little older, questions about family members can work well. I ask "Who has the stinkiest feet?" or "Who has the messiest room?" or even "Who farts the most?" There are always inside jokes and funny times they thing about when thinking of these situations and EVERYONE gets a good laugh.
4. Talk about favorites. One way to break the ice with kids is to get them talking about things they love. They all have a favorite TV show or flavor of ice cream. I don't expect to get many pictures while talking about these things, but it gets them to open up a little bit and be more responsive to other prompts that will get the smile. If they aren't comfortable with you, you'll never get that smile.
5. Lens buddies. Lens buddies are cute little things you can put around your lens and it gives kids something to look at that is interesting, since a big black box with a black round thing on it isn't extremely exciting for kids. I have some friends that have crochet ones and some that are felt. I made my own from an old scrunchie (yes, I still had some...how old am I???) and a little hand puppet from the dollar store. I have a monkey and a tiger. The scrunchie goes around the lens and the animal sits on top. Easy peasy! I just ask the little ones where the tiger is and they look right at my camera.
What are your favorite ways to get kids to smile?