When your kids do a good deed, surely they deserve to get reward and compliment. It is you who have to notice whether they do something good or not. Sometimes they are willing to do something good without telling you before. Imagine how proud and happy you are when your kids told you about the positive things they had just done without your instruction. They have applied what you have explained before and again they deserve to get reward. Indeed, your children, just like the others, are unpredictable. Sometimes they can be good and sometimes they cannot be controlled. You may offer some rewards to attract them to keep their good behavior and attitude. However, you have to make sure that you promise only the positive rewards.
Going to fast food or junk food restaurant is not considered as positive reward. Once in a month, it will be fine to go there. Notice that your kids will love to go there. But, you cannot offer this as a reward. Explain that they need something more nutritious to consume and to make them healthier and smarter. Choose a restaurant which will provide healthy food as a reward. Commonly, parents promise to buy toys as the reward. Yes, toys are considered as good option but you have to choose only the educative ones. Some kids want to have certain toys because their peers own them, not because the toys are educative and valuable. That is why, you should search the toys that can give positive improvement to your kids based on their age. Toys which can be played with friends or sibling will be fine since they can increase the social ability.
Another reward you should put on the top of your mind is offering your kids to visit museum and amusement park. This can be done in the weekend. There must be some interesting places around the town, or you may go to the nearest town to visit the museum. You may also think of simple reward that will please your kids all the time. Special food can be the reward. Since your kids have done something good, you may show them your hard effort to cook delicious food. Let them choose the food from the cookbook and let them see you cook. This will make your kids understand that something good deserve to get something good also. Whatever your reward for your kids good deed, make sure you choose the positive ones.