In the UK we call that game something different but it's so long since I had to play it with Scouts I can't remember what the name was

Anyway, it's based on a supposed military incident in, I think, the Boer War. The message "we are going to advance, please send reinforcements" was sent down the line and arrived as "we are going to a dance, please send three and fourpence" (three and fourpence meaning three shillings and four pence, which was the British currency at the time)

You could try using the original message and see what your Tiger Cubs make of it