One day at Cedar Grove Elenemtary School, Cristina Neri's best friend, Katie moved to Arizona. I was very sorrowful when I saw Cristina crying. At recess, I encouraged her at the swings. Cristina felt much better. The next day, I shared my Hot Cheetos with her. Cristina began to have pleasent feelings about me. We were in inseparable. In a late afternoon, Cristina announced that she is moving. I knew i would miss her very much. She knew she would miss me as much. Then Cristina added cheerfully, "You are a loyal and a true friend." I was honored. I've never forgotten Cristina Neri since that day and on.
Hmm a few comments on that:

The first sentence (One day at Cedar Grove Elementary School etc.), seems very wrong, because I doubt that Katie moved at the school. Maybe you could describe what the weather was like on that day, for example. Maybe it could be gloomy and rainy so as to reflect Cristina's mood, and then when you've cheered her up, it stops raining and the sky is blue and the sun is shining again. What do you think? I'm thinking of something along the lines of:

It was a dark and stormy day, and my mother had just dropped me off at Elementary School. (* the full name of the school is a little uninteresting, but if it's important then leave it)
I spotted Cristina sitting (on th stairs, on a swing in the playground..whatever). She was crying, and I suddenly remembered that her best friend Katie had just moved to Arizona. I felt a sudden burst of great pity for the poor little girl. The bell rang and I had to go into class.

At recess, I saw her, alone again, and I approached her with a sympathetic smile on my face. I tried to reassure her as best as I could at my tender age, and she seemed to feel a whole lot better afterwards. The sky had finally cleared up and the sun was shining it's golden warmth on us once again.

The next day I shared my Hot Cheetos with her, and she was incredibly grateful. We were inseparable after that, and I could tell that she was ecstatic about her new found friend. I was too, of course. Unfortunately, all good things come to an end, and this was no exception.

One day, as we walked home together in the late afternoon, she suddenly announced that she was moving away. I was heart broken. We knew we'd both miss eachother terribly and life just wouldn't be the same, but we could do nothing except make the most of the time we had left together. I remember her saying to me "you are a true and loyal friend". I felt so honoured to have this girl say those words to me.

Cristina Neri is a person who I will keep safe in my thoughts and my heart until the day of my death.
Reading the first one, I felt a little confused. Because for me, " I " appeared suddenly.

After adapation, the story sounds a bit more reasonably. I still wonder why We should add the weather atmospher to it, which looks artificial.