Ghost Photos
In the first tunnel, take pictures of the purple myst that floats around. When they develop, It will be one of the ghost trio (Gastly, Haunter, Gengar).
Group of Charmanders
To find a group of Charmander, go to to the place where you can find the Moltres egg. The pelt the egg with pokemon food, and if you've recieved pester balls, throw those. Then you'll see a Charmander call his buddies. From then on, it's a waiting game. After the Charmander come, take a picture and you'll recieve bonus points from Professor Oak.