Curtains for my sisters classroom. She teaches 1st grade, and has a Dr. Seuss theme, she asked if I would make her curtains, so we found the fabric online (and it was an excuse for me to buy more fabric hehe) and I sewed them up. They actually didn't take THAT long, I serged the edges so I only had to turn them over once. I think the hardest part was making sure they were both the same size!
I have only made curtains one other time, and I hadn't realized that you were supposed to use double the width of the window! but I made sure it was big enough this time!