My mom is a elementary school teacher but I dont know a lot about what she does.
 An elementary school is the main point of delivery of primary education in the United States, for children between the ages of 4–11, didn't you go to one? 
I did but It has changed a lot now im sure.
yeah that is true, In 2001, there were 92,858 elementary schools.
That is a lot but i guess that is because of the population here in America.
Yeah elementary school is usually for students between kindergarten and fifth grade.
I think when I went its was kindergarten to fourth grade
Wow I never knew it was ever that short, I went through sixth grade. in the fall of 2009 almost 3.5 million students attended elementary schools.  
I hope they keep the grades seperated. its only a matter or time before they try to make everyone go to school together I feel.
I don't think there is anything wrong with mixing grades in fact, Primary education tends to focus on basic academic learning and socialization skills.