Harry Potter And The Chamber Of Secrets

Search the left side of Hagrid's Hut, by the Herbology Center. From there, they all scatter (much like Neville's china set) behind Hagrid's Hut towards the Forbidden Forest. The person that wants these will give you the key to the Confiscated Items Room (six more cards and a bag to hold 200 Bertie Bott's Every Flavored Beans).

When you do not want to be hit by ghosts and lose all your items (Balloons, Beans, and sometimes Stink Pellets) just stand on the ledge until the specter nears you. Tap the Analog-stick so that you will fall and catch the ledge. When you are hanging, they cannot hit you and cause your items to go flying.
Another way to avoid the ghosts and keep from losing your collected items is to use Lumos. Hold Down to maximize the spell. The ghosts will not hit you when the light is on. Sometimes this requires careful timing because you are trying to search and collect items at the same time.

Once you enter Diagon Alley, there is a way to avoid Ginny and Mrs. Weasly. Stay against the left wall and you will be able to avoid them. Also, when you finish getting all of Ginny's lost things, stay against the opposite wall of where they are (opposite of Florrish and Blotts) and remain close to the wall.

Use the Skurge spell on a chest covered in ectoplasm behind a tapestry (you need the scissors spell) on the third floor, by the Defense against the Black Arts classroom.

Gather every item for the students around Hogwarts (not the Notice Board). You have to actually find the people. The final person will give you a key to the confiscated items room. In there are six Wizards cards and the biggest Bertie Bots Bean Bag.