Martial Arts School
The best place to host a kids Karate birthday party is at a Martial Arts School. If your child is taking karate classes (which is probably the case) then ask the school if they host karate birthday parties. Most schools will host a karate party at an affordable price. By having your kids karate party at a martial arts school you will minimize safety concerns since the professionals will be there. Typically you will supply the party supplies and food. The school will provide the entertainment in the form of karate lessons, demonstrations and games.
Your decorations can be minimial as the location is your "decorations". If you want to add something bring black and red streamers and balloons. Use karate themed party supplies (plates, napkins, tablecloth).
There is not much else to do. The school will take care of the party activities.
Karate Party At Home
If you are having a Karate Party at home you can still decorate with karate themed products and use a black and red color scheme. Since you don't have the Karate school as a locale you will need to provide more decorations.
Hang posters of Kung Fu artists such as Bruce Lee, Jackie Chan and Chuck Norris.
Greet each child with a Karate headband when they arrive.
Have a Karate Pinata, but lower it enough to allow the kids to kick it as opposed to hitting it with a stick. If the kicking takes to long then pull out the stick.
Goody Bag Ideas - Karate stickers, karate tattoos, karate lesson book, miniature martial arts figurines and candy. Use empty Chinese food containers as the favor bag.
Chicken Nuggets with Sweet & sour dipping sauce.
Fortune cookies for dessert!
Be creative and make a few fun food items look like sushi or use chopsticks.