If you don't want to read the whole saga, answering this question should suffice:
How would you handle a situation where your 4 year old is constantly badgered and annoyed by another 4 year old in her class? Two times you have seen this occur is when you are at pickup and they are on the playground. What do you say to your child to help her deal with the mean kid?

Example 1: Your child and another child are playing nicely together. This child rushes into the area where they are playing and takes things from them and says she was playing with them first.

Example 2: Your child and another child are playing together. This other child rushes over and starts yelling in your child's face, "RED LIGHT, GREEN LIGHT". Your child doesn't know what that means, says something to the child but the child ignores her and keeps screaming in her face. Your child and runs over to you saying that child is mean. That child runs over and says your child is being mean.

How do you handle this with your child? What do you say to them/how do you help them deal with the mean kid?

**At drop off, we let her play with her friends before leaving, which is why we see some of these things happening. The teachers do not watch the kids on the playground, they spend outside time socializing so it's each kid for himself on that damn playground.

**edited out the word "jerky" so people don't get offended.