I was just looking for some materials to help my class become better at researching and found the awesome self help guides from the library.
The library self help website that has TONS of tutorials and videos on how to research and also write reports. It is designed for uni students but I think it is still useful for the last year of high school as well! Particularly I am going to use http://www.otago.ac.nz/library/modules/power_searching/ which is about making effective online searches. And there are a bunch of resources on Google searching on the right hand side.
Also if you click on how do I improve my essay writing and report writing skills on the left hand side there are links to tutorials on essays, scientific reports etc