EMA is like a special wooden postcard that people in Japan use to make wishes at Shinto shrines. Imagine you go to a magical place where there are lots of pretty decorations, statues, and buildings. This place is called a Shinto shrine, and it is a place where people can come and pray to special gods called kami.
Now, when you go to this Shinto shrine, there is something special you can do to make a wish. You can buy a wooden postcard that is called an EMA. An EMA is made of wood and has pictures and decorations on it that are really pretty.
Once you get your EMA, you can use a special pen to write your wish on it. Your wish can be anything you really want, like for your family to be happy, or for you to do well in school, or even for your favorite sports team to win a game!
After you write your wish on the EMA, you can hang it up on a special board at the Shinto shrine. This board is called an EMA board, and it is covered in lots of other EMA from other people who came to the shrine to make wishes too.
So, in short, EMA is a special wooden postcard that you can buy at Shinto shrines in Japan to make a wish. You write your wish on it, and then you hang it on a special board at the shrine with all the other EMA from people who made wishes too.