gistfile1.txt

File.open('homeworkdata.txt', 'r') do |f|
  while line = f.gets
    lines = line.split(',')
    grades = Grade.new(*lines)
    puts grades
    grade_arr << grades
  end
end

OUTPUT
session03       : 5
   
session04       : 5
   
session05       : 5

INPUT
session03,5
session04,5
session05,5