First, natural renewable resources are good to use because they are renewable.
Let's think about the gasoline we use in cars. Gasoline is a non-renewable resource, which means that we're going to run out! Someday, there won't be any gasoline left. We'll have to think of something else to use to run our cars!
If you use non-renewable resources, you're using something that cannot be replaced and will, one day, no longer exist.
Now let's think about trees and wood. Wood is a renewable resource. So long as we take good care of the forests, we will never run out of wood!
This brings us to an important point. You can't just use renewable resources any old way you want to and think it will always come back! You have to manage your renewable resources! Managing resources just means taking care of them.
For instance, managing forests and trees means that you have to take care of forest soils and water, harvest the trees correctly, and most times replant the trees you took.
In other words, renewable resources are renewable only if you take good care of them!
Of course, wood and trees aren't the only renewable resources; Wind, solar power, and hydroelectric power are other examples of renewable resources! So long as we manage these resources correctly, we will alway be able to use them.