The activity I chose is Draw Your Own Constellation. I would start with a discussion about what people would have done at night before electricity , tv etc. to show the children the importance of storytelling and the connection that people had with the natural world. Light pollution could be brought into this as well as dark sky reserves. Then I would tell them some myths and legends about the constellations from in-the-sky.org.
Following that I would show the children simple pictures and names of constellations and ask them to match the picture and the name and to explain their choice. This should help them to visualize connecting the stars to create a whole image.
I would then use Stellarium to show them the night sky. Stellarium gives you an option of viewing the night sky with or without the constellations marked. I would ask the children to try and spot constellations before revealing them.
I would use dot / graf paper at the start when encouraging the children to create their own constellations. I think the structure may help them create a picture and could tie in with math. It may also help them understand that they are not a perfect outline of the intended image. At the start their partner could join the dots to reveal their constellation. When the children are more comfortable creating their constellation they could draw some free hand.
Follow on activities could be night sky art drawn with the children lying under their tables and their paper tacked above them or a creative writing / storytelling activity creating their own constellation story.