What you would do

Write problems with randomized values and a derivation that checks out step by step, such as a charged particle moving through crossed fields.
Grade model solutions for units, signs, approximations and limiting cases.
Find where a model’s derivation breaks, such as a dropped factor of 2 or an approximation used outside its range.
Check answers with a quick numerical simulation or an order-of-magnitude estimate.
Write rubrics that separate a correct method from a lucky final number.

What we look for

You study at or graduated from a college or university in physics or a related field.
A derivation, simulation, measurement or project you did yourself and can explain in depth.
Upper-level coursework in at least two core areas, such as mechanics, electromagnetism, quantum or statistical physics.
Comfort with limiting cases, dimensional analysis and order-of-magnitude checks.

Task size: Tasks take about 30 minutes to 5 hours. Each one shows its estimated time and price before you start, and you are paid that price even if it takes you more or less time.
Pay: Per task accepted in review: its estimated time times the project’s rate. A task estimated at 2 hours at $120 an hour pays $240. Accepted tasks are paid within 30 days.
Hours: Projects last 1 month to a year. Each sets a weekly minimum, usually about 20 hours of estimated work, and you choose when you work.
Tools and review: Your own computer, LaTeX for derivations, and Python or a similar tool for quick numerical checks. Every task is reviewed against the project’s written quality standard before it is accepted.