I have chosen a resource that has a lot of content on teaching kids about creating strong passwords.

https://audreynay.weebly.com/password-development.html

This website has various resources such as printable kid friendly guides to creating passwords, handy tips that can be printed and laminated to be shown in class or placed on wall. There is also videos to share with kids, a link to a password generator site where kids can explore and get examples of strong passwords. The website also has a lesson plan which could be helpful for teachers and many more resources.