Here's my first set of playing cards on the topic: Greetings.
These cards can be used as mini-flashcards to help learning new vocabulary/ structures, or as normal playing cards to revise words.
It's important that each student has it's own set. They can add their initials at the top corner so that they can organize and keep their own materials after playing.
The big HIT you can let your students play with these card is "peixinho" I don't know the equivalent name in English but this game consists on: shuffling the cards on the table, each student picks 4 random cards and the objective is to get groups of 4 equal cards by asking other players for the cards in need.
I believe that students should take an active part in what comes to making some of the teaching/learning materials that's why these playing cards (and the following ones) aren't "ready-to-use". They need to be coloured, cut, and the words need to be traced before students can use them to play.
Have fun! and Keep up the Teaching-Frenzy :)