using System.Collections.Generic;
public Student[] Students{get;set;}
public string Name {get;set;}
public static void Main()
new School(){ Students = new [] { new Student(){ Name="Bob"}, new Student(){ Name="Jack"} }},
new School(){ Students = new [] { new Student(){ Name="Jim"}, new Student(){ Name="John"} }}
var allStudents = schools.SelectMany(s=> s.Students);
foreach(var student in allStudents){
Console.WriteLine(student.Name);
List<string> cats = new List<string>();
cats.Add("American Curl");
StringBuilder builder = new StringBuilder();
foreach (string cat in cats)
builder.Append(cat).Append("|");
string result = builder.ToString();
Console.WriteLine(result);