These two questions are similar so we got Richard F. to answer both at the same time. The scientists have been really busy with your questions but we're trying to anser them all. Here's Richard's answer:

Do you remember the answer to the question, why is the sky blue? The sky is blue whenever the sun shines on it. The sky is so bright in the daytime that you can't see the stars. They're there, but they're too faint to see.

Actually, there have been reports of starts being visible during the day, but that only happens under exceptional conditions.

In the daytime, the part of the earth we live on is turned towards the sun. The sun lights up everything on that side of the earth, including the sky. When night comes, the earth has turned around so that the sun is at the other side. When the sun isn't shining on the sky above you, the sky isn't lit up. It is clear, and you can see the stars right through it, unless it's cloudy, of course. You can't see through clouds. And if you look in a direction where there isn't a star, you don't see any light at all. What colour is it when there's no light? It's dark or black. So that's why the night sky is dark, except for the stars.

REFERENCES FROM THE LIBRARY

Exploring the sky by day/by night by Terence Dickinson.

Why is the sky Blue by Chris Arvetis, 520 arv

Why is the sky blue by Jack Long, 508 lon this one is just what you need to explain these questions more fully.