Why is this the answer?

The answer is calendar because this clever riddle is all about how we keep track of time, and the calendar is the perfect tool for that important job. Think about a calendar you have at home or in your classroom. It is a very special tool that helps us remember what day it is, what month it is, and what exciting events are coming up. The first clue in the riddle is the tricky part: "No matter how little or how much you use me." Imagine you have a brand new calendar for the whole year. Maybe you are super organized and write down every single baseball game, birthday party, and school holiday on it. You might look at your calendar ten times a day to make sure you are on time for everything. Or, on the other hand, maybe you forget about it and it just hangs on the wall, untouched for weeks and weeks. Does it matter how many times you look at it or write on it? No, it does not! Now let us look at the second and most important part of the riddle: "you change me every month." This is the biggest and best hint! Every single calendar, whether it is covered in important notes or completely blank, has to change its page when a new month begins. When the page for January is finished, you must turn it to see February. When February is done, you turn to the page for March, and so on, until you get all the way to December. The calendar is always moving forward through the year, right on time, without caring if you used it a lot or a little during the last month. A calendar is one of the most reliable and steady objects we use. It shows us that time never stops and always marches on. Even if you do not pay attention to the calendar, the date still changes, and the month still ends. That is why it is the perfect answer! It changes its page exactly every single month, no matter what you do, proving that the flow of time is unstoppable. It is an amazing invention for keeping track of our busy lives.