Children and young people aged 10-17 can complete a dedicated youth version of a recognised strengths test which was developed the University of Pennsylvania in the US.
It will take around 45 minutes to complete and answer all the questions, and you will need to sign-up to the site for an account before you can access the survey.
Once completed, the survey provides a rating of their top 5 strengths which are called their "signature" strengths. These can then be used for further development and discussion.
Follow the link here for more information above the survey.
(Click on: Questionnaires > VIA Strength Survey for Children)