gistfile1.cs

// ask the user for a number grade
Console.WriteLine("Hey, what grade did you get on that test?");

// declare variable to hold number grade
int intGrade = -1;

try
{
	// assign grade number from user
	intGrade = int.Parse(Console.ReadLine());
}
catch
{
	//Console.WriteLine("That is not a number, dummy. I have better things to do. Smell ya later.");
}

// declare variable to hold grade letter
string strLetter = "F";

if (intGrade == 100)
{
	strLetter = "A+";
}
else if (intGrade <= 99 && intGrade >= 94)
{
	strLetter = "A";
}
else if (intGrade <= 93 && intGrade >= 90)
{
	strLetter = "A-";
	/*
	* a bunch more else if's to handle B, C, D, E
	*/
}
else if (intGrade >= 0)
{
	// handle zero (or less)
	strLetter = "F";
}
else
{
	strLetter = "You are teh dumb dumb.";
}

Console.WriteLine(strLetter);

Console.ReadKey();