This is a page of cryptograms I made, using http://puzzlemaker.discoveryeducation.com/cryptogramSetupForm.asp. The idea is to solve the puzzle by converting numbers into letters. It is a great way to exercise language awareness (structure, vocabulary and grammar) and acquire some general knowledge about quotes of famous individuals in the process. It can be used in just about any level, except for the very basic beginners. It really depends on the individual learners' abilities. If they're not already familiar with this technique, they usually get the point quite quickly, as soon as they are over the initial shock.