Canada-Wide Science Fair https://cwsf.youthscience.ca/
Links to sites with Science Fair ideas http://scienceoutreach.ab.ca/children/fairs/
Canada-Wide Virtual Science Fair http://www.virtualsciencefair.com/
Science Fair Project Ideas for Elementary students https://www.education.com/science-fair/
Science fair projects with instructions http://www.all-science-fair-projects.com/