thank you all so far, made changes

Errors:
Code:
root@bt:~/gradesystem# make gradeSystem
g++     gradeSystem.cpp   -o gradeSystem
gradeSystem.cpp: In function 'void writeGrade(int, int)':
gradeSystem.cpp:17: error: 'findLetter' was not declared in this scope
gradeSystem.cpp: In function 'int findLetter()':
gradeSystem.cpp:36: error: 'studentAverage' was not declared in this scope
gradeSystem.cpp:37: error: 'letterGrade' was not declared in this scope
gradeSystem.cpp:37: error: 'A' was not declared in this scope
gradeSystem.cpp:39: error: 'studentAverage' was not declared in this scope
gradeSystem.cpp:40: error: 'letterGrade' was not declared in this scope
gradeSystem.cpp:40: error: 'B' was not declared in this scope
gradeSystem.cpp:42: error: 'studentAverage' was not declared in this scope
gradeSystem.cpp:43: error: 'letterGrade' was not declared in this scope
gradeSystem.cpp:43: error: 'C' was not declared in this scope
gradeSystem.cpp:45: error: 'studentAverage' was not declared in this scope
gradeSystem.cpp:46: error: 'letterGrade' was not declared in this scope
gradeSystem.cpp:46: error: 'D' was not declared in this scope
gradeSystem.cpp:48: error: 'studentAverage' was not declared in this scope
gradeSystem.cpp:49: error: 'letterGrade' was not declared in this scope
gradeSystem.cpp:49: error: 'F' was not declared in this scope
gradeSystem.cpp:51: error: 'letterGrade' was not declared in this scope
gradeSystem.cpp: In function 'void saveError()':
gradeSystem.cpp:56: error: expected primary-expression before 'int'
gradeSystem.cpp:56: error: 'nowTime' was not declared in this scope
gradeSystem.cpp:59: error: 'theTime' was not declared in this scope
gradeSystem.cpp: In function 'int nowTime()':
gradeSystem.cpp:69: error: 'theTime' was not declared in this scope
gradeSystem.cpp: In function 'int main()':
gradeSystem.cpp:90: error: no match for 'operator>>' in 'std::operator>> [with _CharT2 = char, _Traits2 = std::char_traits<char>, _CharT = char, _Traits = std::char_traits<char>](((std::basic_istream<char, std::char_traits<char> >&)(& std::cin)), ((char*)(& studentName))) >> std::endl'
/usr/include/c++/4.3/istream:123: note: candidates are: std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(std::basic_istream<_CharT, _Traits>& (*)(std::basic_istream<_CharT, _Traits>&)) [with _CharT = char, _Traits = std::char_traits<char>]
/usr/include/c++/4.3/istream:127: note:                 std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(std::basic_ios<_CharT, _Traits>& (*)(std::basic_ios<_CharT, _Traits>&)) [with _CharT = char, _Traits = std::char_traits<char>]
/usr/include/c++/4.3/istream:134: note:                 std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(std::ios_base& (*)(std::ios_base&)) [with _CharT = char, _Traits = std::char_traits<char>]
/usr/include/c++/4.3/istream:170: note:                 std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(bool&) [with _CharT = char, _Traits = std::char_traits<char>]
/usr/include/c++/4.3/istream:174: note:                 std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(short int&) [with _CharT = char, _Traits = std::char_traits<char>]
/usr/include/c++/4.3/istream:177: note:                 std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(short unsigned int&) [with _CharT = char, _Traits = std::char_traits<char>]
/usr/include/c++/4.3/istream:181: note:                 std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(int&) [with _CharT = char, _Traits = std::char_traits<char>]
/usr/include/c++/4.3/istream:184: note:                 std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(unsigned int&) [with _CharT = char, _Traits = std::char_traits<char>]
/usr/include/c++/4.3/istream:188: note:                 std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(long int&) [with _CharT = char, _Traits = std::char_traits<char>]
/usr/include/c++/4.3/istream:192: note:                 std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(long unsigned int&) [with _CharT = char, _Traits = std::char_traits<char>]
/usr/include/c++/4.3/istream:197: note:                 std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(long long int&) [with _CharT = char, _Traits = std::char_traits<char>]
/usr/include/c++/4.3/istream:201: note:                 std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(long long unsigned int&) [with _CharT = char, _Traits = std::char_traits<char>]
/usr/include/c++/4.3/istream:206: note:                 std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(float&) [with _CharT = char, _Traits = std::char_traits<char>]
/usr/include/c++/4.3/istream:210: note:                 std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(double&) [with _CharT = char, _Traits = std::char_traits<char>]
/usr/include/c++/4.3/istream:214: note:                 std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(long double&) [with _CharT = char, _Traits = std::char_traits<char>]
/usr/include/c++/4.3/istream:218: note:                 std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(void*&) [with _CharT = char, _Traits = std::char_traits<char>]
/usr/include/c++/4.3/istream:242: note:                 std::basic_istream<_CharT, _Traits>& std::basic_istream<_CharT, _Traits>::operator>>(std::basic_streambuf<_CharT, _Traits>*) [with _CharT = char, _Traits = std::char_traits<char>]
/usr/include/c++/4.3/istream:748: note:                 std::basic_istream<_CharT2, _Traits2>& std::operator>>(std::basic_istream<_CharT2, _Traits2>&, _CharT2*) [with _CharT2 = char, _Traits2 = std::char_traits<char>, _CharT = char, _Traits = std::char_traits<char>]
/usr/include/c++/4.3/bits/istream.tcc:858: note:                 std::basic_istream<_CharT, _Traits>& std::operator>>(std::basic_istream<_CharT, _Traits>&, _CharT&) [with _CharT = char, _Traits = std::char_traits<char>]
gradeSystem.cpp:94: error: expected `)' before ';' token
gradeSystem.cpp:94: error: expected primary-expression before ')' token
gradeSystem.cpp:94: error: expected `;' before ')' token
gradeSystem.cpp:25: error: too few arguments to function 'int theAverage(int, int, int)'
gradeSystem.cpp:105: error: at this point in file
gradeSystem.cpp:13: error: too few arguments to function 'void writeGrade(int, int)'
gradeSystem.cpp:106: error: at this point in file
make: *** [gradeSystem] Error 1
here is the new code:
Code:
#include <iostream>
#include <fstream> // open, read, and write files

//for time
#include <stdio.h>
#include <stdlib.h>
#include <time.h>

using namespace std;

void writeGrade(int studentAverage, int letterGrade){
/*
Use the variable gradeAverage to determin the the grade was a A, B, C, D, or F. Then open of the person's file, and write the grade.
*/
  findLetter();
  ofstream gradeFile;
  gradeFile.open ("grades.txt");
  gradeFile << "Student: " << studentAverage << endl;
  gradeFile << "Grade: " << letterGrade << endl;
  gradeFile << "Average: " << studentAverage << endl << endl;
}

int theAverage(int totalAmount, int gradeNumber, int studentAverage){
/*
Here we will average all the numbers together inside of a for loop
*/
  studentAverage = totalAmount / gradeNumber;
  return studentAverage;
}

int findLetter(){
//take the number and find the letter it is == to
//then store that letter in letterGrade
  if ( studentAverage > 95 ){
  letterGrade = A;
  }
  if ( 95 > studentAverage > 85 ){
  letterGrade = B;
  }
  if ( 85 > studentAverage > 80 ){
  letterGrade = C;
  }
  if ( 80 > studentAverage > 69 ){
  letterGrade = D;
  }
  if ( studentAverage < 69 ){
  letterGrade = F;
  }
  return letterGrade;
}

void saveError(){
// save error in log.txt
  nowTime(int theTime);
  ofstream logFile;
  logFile.open ("log.txt");
  logFile << "Date: " << theTime << endl;
  logFile << "Error: File does not exist or cannot be opened." << endl;
  logFile << "Please create file, or create a new file." << endl << endl;
}

int nowTime(){

  time_t now;
  time(&now);

  theTime = "%s", ctime(&now);

return theTime;
}

int main(){
  //startup variables that we will use
  char studentName[255];
  int studentAverage;
  int gradeNumber; // amount of student Averages
  int totalAmount; //will hold all averages
  int submitAmount; //amount submited during for loop session
  char letterGrade; // will store the lettergrade before it is written to grades.txt
  int theTime; // will hold the current time
  bool canWe; // asks if we can continue
  

  // find out who we will be grading
  cout << "Hello user!" << endl;
  cout << "This program lets you average the grade of your student and write there grade in a text file." << endl;
  cout << "Who will be writting a grade for today?" << endl << "Name: ";
  cin >> studentName >> endl;
  cout << "Ok, we will be grading " << studentName << "today!" << endl;

  // make a loop for finding out the average
  for ( gradeNumber; canWe == true; gradeNumber++; ){
  cout << "Please submit the next grade." << endl << "Grade: ";
  cin >> submitAmount;
  submitAmount + totalAmount = totalAmount;
  cout << "Thank you, the grade has been added." << endl;
  cout << "Would you like to add another grade or would you like to quite?" << endl;
  cout << "Type 1 to contine or type 2 to quite and press <enter>." << endl << "1 or 0: "; // may need to be switched to true or false
  cin >> canWe >> endl;
  return totalAmount, gradeNumber;
  }

  theAverage();
  writeGrade();
  

return 0;
}
Will be working though this myself to see what I can do, but any help is appreciated.