Donating plasma can actually work out better than selling your blood. It takes longer to donate plasma because they will put your red blood cells back in your system. The upside is that you can donate plasma as much as twice a week and you can make anywhere from $40-$60 per donation. You can make that $100 in less than a week if you can stomach the needle.
One great way to make money as a kid is to do odd jobs around your home or neighborhood. For example, you might be able to mow the lawn in exchange for allowance money, or offer to babysit a neighbor’s younger children. If you’re crafty, try selling stuff you’ve made online or at a local arts and crafts fair. You may also be able to make a little money by making helpful or entertaining videos and posting them on YouTube!
Even if it’s a mundane task like walking dogs, you could start the next (or only) full-service dog walking and grooming service in your town (where dog owners rave over your business and always refer you to others). You can also hire other dog walkers as you grow, and turn your side hustle into a sustainable enterprise. You just have to do the work, and do it well.
If you already have a website or blog, look for vendors that offer related but noncompeting products and see if they have an affiliate program. Stick to familiar products and brands—they're easier to sell. For promotion, place simple text or graphics-based ads in appropriate places on your site; you can review or recommend products or create a dedicated sales page or website to promote a particular product.
Amazon makes it fairly easy to list and sell old books, games and devices on its marketplace. You can make more than just a few bucks If you have pricey textbooks from college. Be sure the books are in good condition. You'll get negative reviews if you attempt to sell books that are falling apart or games that are scratched up. Remember, be upfront about any defects, no matter how small they might be and no matter how few people might readily notice it.