Get in the Kitchen! I was very hesitant for a while with my son when it came to the kitchen. I worried about the GIANT mess that would be left when he was done "helping". You don't even have to take on the entire project with them! You can start small and let your child help with measuring certain ingredients. You can modify the difficulty of the 'lesson' by talking about the different kinds of measuring cups and seeing what other measurements can also add up to equal one cup, etc.
Children can take classes from various organizations that will support their mathematical development. These organizations may offer classes in the summer or on the weekends. Some of the classes can teach children how to build robots, toy cars, toy airplanes, etc. These classes may be in the area of engineering, computer science or some other technical field.
Go Shopping! : You can cater this to all different ages. For young children, you can do a 'mock shop' and let them pretend to go shopping in a pretend store (your kitchen). Label certain items with easy to read prices and print some pretend money for them to shop with! For older children, you can let them help you in the actual grocery store with a specific shopping list. You can even set specific spending limits and give a specific amount of items and let them determine what they can afford, etc.
For example, some programs use incentive tools similar to those found in video games. Each time a child completes a satisfactory score on a worksheet, the program congratulates them and gives them a score. With each level, the score increases. After a certain number of points, the student reaches a named level, such as captain or commodore.