The one I am showing you here is a bit simpler using paint and very applicable to the younger (k-3) grades.
On watercolor or sketch paper have the kids draw a skyline in pencil from one side of the paper to the other. We did not use a ruler..... going for a free form design but by all means have them use one if you are developing those ruler skills.
This picture is from the other skyline post. You can have them outline the picture in marker or in white pastel which is how Grade 2 did it.
Using disk tempura have the kids paint their skylines in bright colors. Leave the painting to dry and then cut out.
The kids now have a choice of making a daytime background or a night time background.
For a daytime picture we took a blue piece of posterboard and sponged on some white clouds with white liquid tempura paint.
For a night time scene we used black posterboard and using a splatter box hit a brush loaded with white paint against a dry paintbrush to create stars. The student here is creating some large constellations!
When the background has dried we glued the skyline into place.
I placed each finished skyline between artboards with wax paper on top. I then weighted it down so they would dry flat.
That's it. Amazing skylines Grade 2!
Great project with terrific results and very easy to execute. Give it a try!