Usability Testing with kids

I am currently studying Multimedia Design at Business Academy Aarhus, Denmark, and we are learning a lot about UX Design. I am working currently on a project about Usability testing with kids and I want to know your advice about that. Can you share what challenges we should consider and some tips for performing good testing? If there is anyone experienced in this field I would like to conduct a short interview. I am trying to collect information from experts in that area. You can also connect me with somebody who might be interested to help. It will be very valuable for my project.