Interact with the train and you automatically get all the memory links. Click on the train again to transport to the next memory.
In the carnival, turn right and interact with Johnny and his family who are standing in front of the whack-a-mole booth.
Go ahead and play the whack-a-mole after they leave. Actually you really need to. So go on ahead and play to get the first memory link.
Follow Johnny to the fortune telling booth and interact with his mom to get the next memory link.
Now head down to the ferris wheel and speak to the man that's jumping around beside it. You'll gain a memory link from him.
Go all the way to the right and head south towards the bridge that leads to the next area.
There are two memory links here. For the first one just climb onto the stage where the choir's singing. The other one you'll receive after interacting with Johnny who's eating at the table to the south.
Follow Johnny to the playground and keep on following him as he strays further into the cliff. A cutscene will play once you get there.
After the cutscene you'll find yourself back at the school. Exit the cafeteria and make your way to the right side of the hallway. Follow Eva.
Make your way through the obstacles that Eva placed to stop you. Try to avoid stepping at the spikes or you'll get sent a couple of steps back.
Keep on heading for the right side of the hallway. Dr. Watts will remark that it's a looping hallway and you'll eventually break out of it.
Once you've created a hole in the wall, pass through it and you'll find yourself in a similar hallway. This time just keep going left and answer the phone when you find it. Enter through the door and watch the events unfold.