How can you explain how we see the moon during the day to your teacher? The moon is visible in daytime because the apparent brightness (m) of reflected sunlight off the surface of the moon essentially exceeds the brightness of the blue sky, unlike the stars. That’s your simple answer.
Apparent brightness is the brightness we perceive after light passes through our atmosphere to our eyes.
Our sun and objects that reflect our sun’s rays are very bright in comparison with their surroundings. Any magnitude below -4 cannot be seen in daytime (the lower the number the brighter the object). Our sun is -26 and the full moon is -12.5, well above the magnitude necessary to see in daytime, -4. The brightest star has a magnitude of -1, dimmer than the required -4 magnitude required to be seen in daylight. All other stars are dimmer still.