i'm not sure but i do know that all of the doman flash cards and the YBCR flash cards are a good size... much bigger than adult flash cards. the print is huge, too! so take that into account when you are making yours. the YBCR are 5X8" or 6X9" or close to it. they are the size of the large sticky notes. what i do is when we're done with the english, i sticky a foreign word over it to help with our languages. that is the nice thing about flashcards with pictures... you can reuse them learn other languages!
hope this helps!
the doc