You are using single quotes in the PHP, which means it won't parse the $shellvar as a PHP variable. Then that is getting passed to the terminal, which tries to use the variable (which doesn't then exist) and it spits back a blank variable. So try replacing the single quotes with double quotes in the shell_exec command.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.