I can't find a way to create new files fast, like the good ol' ctrl+n.Ctrl-Shift-N will create a blank file. (At least in my version it does; the wiki-page (http://wiki.codeblocks.org/index.php?title=Keyboard_Shortcuts#Files) says it is just Ctrl-N ??)
mkdir temp
cd temp
touch filename1 filename2 filename3 filename4 filename5
for a in *; do cp $a $a.hpp; mv $a $a.cpp; done
mv * ..
cd ..
rm -r temp