From reddit: http://www.reddit.com/r/matlab/comments/1ytrq5/i_have_this_code_for_checking_student_grades/

Omar_Prieto_Problem1.m

% Problem 2

prompt = 'Would you like to check your grade? (Enter yes or no)';

str = input(prompt, 's')';
if isempty(str);
    str = 'yes';
end;

prompt = 'please enter your score';
result = input(prompt);
s = result;
if s >= 89.5 && s <= 100;
    disp('Your overall scrore is an A');
elseif  s >= 79.5 && s <= 89.5;
    disp('Your overall scrore is a B');
elseif  s >= 69.5 && s <= 79.5;
    disp('Your overall scrore is a C');
elseif  s >= 59.5 && s <= 69.5;
    disp('Your overall scrore is a D');
elseif  s >= 0 && s <= 59.5;
    disp('Your overall scrore is an F');
else  s > 100 && s < 0;
    disp('Invalid grade entered');
end;