Here are the images I have taken for the ISO home work. The exif data is displayed on each image. If you follow the link below you will see all of my albums. The ISO one are labelled.

The first album displays 5 images each with a changing ISO but a constant aperture of f/8.

The second displays 5 images each with a changing ISO a constant shutter speed of 1/80.

http://s821.photobucket.com/home/DannyEustace/index

Although there is not that much difference between each of your images which is what I wanted to see, you can clearly see that by using the higher iso introduces more grain to the photograph. Good examples of the task