] I love making small ATC cards for Pocket Letters. I also love to add them to other projects too. So your challenge this week is to make an ATC card and add it to your project. ATC cards are 3 1/2 length by 2 1/2 width. You can choose any theme you would like. You have until Oct. 3rd to post your creation. Here is my example... My card is 4x4.