What should I do for my Student Portfolio under the 'Best Work' requirement?

I am applying for an amazing school , and I need to complete the student portfolio pretty soon. The only part I have left is best work, which is where I submit my ‘best work’ for a variety if subjects. Long story short, I have to make that best work now for a variety of reasons. This school is a Science and Math institute, and an art school. So, I need best work for Social Studies, Math, Science, and English. I already have English figured out, Im doing an essay.

There is no possible way for me to use a piece of work ive already done its impossible and wont work for several reasons Im too lazy to explain aha.

I need something High-school level that I can do at home, and either have it on paper or video.

I can only do one a day so I need the work/expirement to take no longer than a day..

For science Im kinda thinking an expirement where I can record data or something, please dont suggest a volcano though lol. Math I just need something thats more than an average worksheet that will demonstrate my capable abilities and whatnot. For Social Studies Im absolutley clueless though.

             Any Ideas? Thank youu