You could try this:
One of my former university teachers, Martin Poliakoff, is a professor in Inorganic Chemistry at The University of Nottingham in the UK.
His team are producing a version of The Periodic Table which aims to have a video on every element on the table which you access by clicking on its symbol.
I have found this a great teaching resource. Your son may find it interesting to use at home.
For example he could go down group 1 and group 18 and see the trends that occur in the reactivity of the elements. These can be very spectacular reactions.
The team have access to some very exotic substances which you do not normally see in conventional educational resources.
Here is the link. I hope this may be of help.