Daniel Russell's Search ReSearch activities and Dan Meyer's strategy of using videos and pictures to prompt students to ask math questions.
When I show the picture to the left during my workshops (click it to enlarge it and feel to use it yourself) I simply ask people to share the questions that come to mind when they see it. Then I give people time to try to use various Google search strategies to find the answers to their questions. Sometimes people find the answers and other times they don't. It's okay if they don't find the answers because the point is to try a variety of search strategies.
Some of the questions that are frequently asked about the picture are:
Where was this picture taken?
How big is the truck?
How much fuel does the truck consume?
How big are the tires?
All four of the questions above can be answered by using various search strategies and tools. Using the "similar images search" in Google Images will help you answer these questions. Google Maps Street View will help you answer the questions too. And while not essential to answering the questions, refining your search to a specific top-level domain could help too.
Create your own image-based search lessons.
Besides taking your own pictures and putting them online, a good strategy is to use Creative Commons-licensed images from Flickr. I recommend Flickr because many of the images are tagged with locations and some have captions that can give your students a few clues to work with.
For pre-made search lesson activities, take a look at the Google Search Education page.