1) Download, open and link the Google Drive app to your Google account. I use my personal iPhone because the iPad I have from my school is an iPad 2 whose camera is horrible.
2) While in the Google Drive app click the plus sign (+) in the top right corner.
3) In the menu it brings up, choose "Use Camera" at the bottom.
4) Take a picture of your students work and click "Use Photo." If you do not like the photo you can choose "Retake" instead.
5) After you take the photo the app will automatically upload the photo to your Google Drive account. It will put it in your main Drive folder. To see the progress of the upload, open the menu and click "Uploads." It usually takes about 30 seconds to upload the file.
6) In Chrome open the picture file in your Drive account and show the class their work. If you have a hard time finding the file (it usually names it "Photo Date Time") open your recent items and it should be at the top of your list.