I've done this project for the past 5 years and it is ALWAYS a hit. Students love it. It is a standard project of taking a smaller image and recreating it on a larger scale.
It involves MEASUREMENT, DILATION, and NUMBER SENSE.
Honestly, drawing skill isn't really needed.
This project includes step by step directions on how to find images, print them correctly, make the small grids, the large poster grids, and finally how to transfer the image.
This is the BEST end of the year project. Stu