Adding namespaces

First, we need to add a couple of namespaces. To do this, enter the following under using System near the top of the file:

using System.Linq;
using System.Collections.Generic;

Creating the student class and defining fields

Next, we will make a class called Student. Above the line beginning with public partial class _Default..., enter the following:

public class Student

Next, to define fields, enter the following between a set of curly braces below this line:

public string Name { get; set; }

So, little properties here, and then let's add one more. Enter the following below this line:

public List<int> Grades;

Here, List<int> is for the grades of the students, and let's name it Grades.

Making a list of students

Now, in the next stage, we will make a list of students. To do this, start by entering the following between the set of curly braces after the line that begins with protected void Button1_Click...:

List<Student> students = new List<Student>

Here, students...