Science Buddies has some interesting ideas
All Science Fairs have some very inspiring physics projects.
Some great extended project ideas here: 300 stimulating ideas for IB Physics Practical Investigations & EEs.
There is also the Physics Review periodical in the library that has articles, many of which are of an appropriate standard for IB Physics.
The International School Bangkok have compiled a real science journal of successful student projects and Extended Essays.
See all the Extended Essays in Physics from UWCSEA - Dover and East -- in the library catalog here. Remember: essays from 2006 onwards were grade A or B. And you can read them freely online.