Here are 5 guidelines for remote testing with children between the ages of 9-12.

1. The more you can see each other, the better
The great thing about remote testing is to be able to be comfortably set up at home or at the office, without the stress of a new environment that you can’t easily control.
But when testing with children, it’s a different story.  Interaction has to be more personal and visual:  the webcam makes discussions flow more easily and creates trust and cooperation, which audio alone can’t do.
In our first testing sessions, we started our webcam at the beginning of the interview to say hi to the child and to introduce ourselves, and then we turned it off so they could concentrate on the task.
This was a mistake.  It’s a lot easier to keep their attention if you see each other and you can reassure them that they’re not alone behind a monitor listening to a voice that’s giving them tasks to do.
On the facilitator’s side, by seeing the child’s environment (posters on the wall for example), they can more easily create a link to those objects and make the task scenario more credible.
For example, “Imagine that you planned to see a show with your friends” would become “Imagine that you are going to a tennis match with Roger Federer” (if tennis posters are on the wall), since this doesn’t bias the task or the results.

2. Decoding their language
From experience interviewing adults, you might expect that children understand your questions and that they will be as expressive and direct in their comments.
But in fact it’s just about the opposite, and many articles address the issue:  No, children don’t always understand what you ask them (and won’t always have the courage to tell you).  Yes, they can throw you off balance by having little to say, and yes, they are more concerned than adults about pleasing you.
There are several strategies to deal with this:
-Be simple and brief in your instructions.  Task scenarios should have a single and specific goal.
-Ask them to reformulate the task in their own words, to be sure they’ve understood.
-Avoid closed questions that require only a yes/no answer.  Instead, use open questions that invite thought and discussion.  For example, “Why…”, “What do you think of…”, “What could we do to improve things in your opinion?”
-When you point to things on the screen, be precise, especially in remote tests.  For example, “At the top right of the screen, there is an image.  Under this image, there is some text that says … Do you see it?”
-Change the tone of your speech according the age of the child:  An “enveloping” tone appropriate for a 9-year-old will be judged as condescending by an 11-year-old.
-There will probably be words and expressions on the screen that aren’t understood by participants.  Don’t hesitate to ask them what they’re referring to:  “What does ‘A hero’s mettle’ mean to you?”  This will help validate the terminology in the site and identify which terms to use.

3. Make them into accomplices
When they don’t answer, or if they hesitate or don’t seem sure of what they should say, tell them that you don’t understand and you need their help (but without losing your credibility).  For example, “I don’t understand what they mean here […] – what do you understand?”

4. Technology experts?
They might be born with a Wii in their hand, but don’t overestimate their capacity to make the technology work.  The presence of parents in the near vicinity can help in case of a technical problem.

5. Change it into a game: “Would you like to go on a mission?”
In their article “Teenage Usability: Designing Teen-Targeted Websites”, Hoa Loranger and Jakob Nielsen mention that as the levels of reading, patience and search are lower in children, it’s important to try to motivate them.
-Be sure to get their attention before proceeding:  Ask questions by mentioning their first name, for example, “Lisa, how could you find this information?  Can you show me on the screen?”
-Transform the task into an important quest:  If the child started the task and isn’t sure what to do,  prompt them with “What do you think we should do here?… Ok, let’s do that.”
-Make sure tests don’t last longer than 45 minutes.
“Lower reading levels, impatience, and undeveloped research skills reduce teens’ task success and require simple, relatable sites.” (Nielsen)

And not to mention…
We can’t repeat often enough how important it is to get the consent of parents for tests with minors, to ensure the ethical integrity of the company doing the interviews.
It’s also essential that parents be present during the introduction period. Afterwards, they should be in separate room so as not to influence the child’s comment, but close enough to be available in case they’re needed.

Sources:
http://blog.usabilla.com/usability-testing-with-children-a-lesson-from-p…
http://fr.slideshare.net/di8it/8-guidelines-for-usability-testing-with-c…
http://www.nngroup.com/articles/usability-of-websites-for-teenagers/
http://www.askdrsears.com/topics/discipline-behavior/25-ways-talk-so-chi…