The activity set that I would choose is The sun and Shadows as I think there are many different activities that you could do to investigate these, a lot of which are hands on and would grab the children’s attention.
I think the children would really enjoy creating a sundial and observing it over the course of the day. I think they would find it interesting to observe how the shadows move and change as the sun moves throughout the day.
Another activity to try with them would be tracing each other’s shadows with chalk in the playground. I think that they would have a lot of fun with this. They could then return outside later in the day and compare their shadows standing in the same position. They could then experiment further indoors with a lamp to mimic the sun, observe and trace different items in the classroom and see how the height and distance of the lamp changes the shadow.