Ahhh .. some kids (or maybe most of them) are just not fond of cleaning up after their play. For a lot of parents, teaching kids how to clean and organize their room is really a challenge to do since they always rely on their parents or their househelp to do the task for them. However, they really need to learn this task so they can be responsible.
Most of the times, parents force them to clean and organize to the point that they argue or fight over this task that often resulted in crying, shouting, scolding and even giving the kids sanction or punishment. Kids need to grow up and learn how to do things on their own for they can't be with their parents all their life.
Talk to your kids about this responsibility at home and tell them how important it for them to do it. Show your kids how to clean up and organize and for sure in no time they will have the hang of it. Give them rewards like paper stars, their fave food, a trip to the zoo and other simple rewards that can encourage them.
Tools for cleaning and organizing can be very helpful as well. There are clear plastic containers available where they can put their toys after play or their writing tools. Colorful containers with characters or other designs can be used. Trunk Chest and other similar containers or lockers can be a good place where they can put all their belongings. They can even put labels or stickers on those storage boxes to make it more fun
Let them do the clean up and storage so that when they also need something they know where to get it. Lastly, always remind them that task if you know that they are forgetting it again and always give them support and encouragements.