Answer:
Well a subject that you can write in depth is like space and NASA and like that or very complicated science topics or just imple physics. Like for science for example you can write a mouse trap car and explain the physics and the designs and how the best design can make make the longest distance or the fastest speed. You can watch a you_tube video, just search up “Mouse trap car Mark Rober” and you should be fine. That should take up 30 pages. My planing would be,
1-3 pages for the basics and ow it works
4-8 pages for the design and how it works
9-15 pages for the explanation how a mouse trap car works
16-20 pages for the best designed or list like Aton of designs
21-25 pages for the history of it
26-30 pagees for ending