Oh, my! That is quite a comprehensive list of ways to make extra money. I think many folks are looking to make an extra buck – especially online. And somehow just because it is online, they think it should be easy as well. My experience is that most of the money making ideas are good but need persistence and follow up before they start generating serious coin.
Find a profitable niche. Starting with your interests, write down as many niche ideas as you can. Think about topics people might search online. Ideas include passions (like surfing or body building), fears (like spiders or speaking in front of crowds) and problems (like getting out of debt). Do keyword research to see it others are interested in the topic. Find out if a domain name is available that matches the keyword 100 percent. 
LeapForce and Appen Butler Hill are two major firms that hire search engine evaluators. (Appen also hires social media evaluators, who analyze the relevancy of a company’s social media news feed.) Appen has potential employees complete an application (project-specific screenings and language proficiency tests may also be required), and LeapForce asks candidates to take and pass a three-part qualifying exam. Both companies also require that you have a new computer, smartphone, high-speed internet, anti-virus software, certain operating systems and be a little internet-savvy.
Roofstock – Investing in rental properties is one of those passive income ideas that can be extremely intimidating, especially when it comes to finding tenants. Roofstock lets you buy properties with as little as 20% down that already have tenants living in them. That means you start getting paid from the first day of your investment. You don’t even have to physically visit the properties!
Buy a small business: A local small business, like a car wash or a laundromat, is a great way to put money down on a money-making venture. Automate it so you don't have to be on the premises unless you're collecting money. Go into a local business with your eyes wide open - study the books, especially on income and expenses, and examine water and utility bills if your venture will be open 24 hours.
If you have a background in a specific field, you may find there is a demand for writing industry papers in your area of expertise. For example, there are often adverts for doctors, lawyers, nutritionists, and business experts from particular niches, to write white papers on different subject areas. These are well paid jobs that you will need to stake your reputation on, but that can often be worked on from the comfort of your own home.
There are also shopping apps like ibotta, MobiSave, and checkout 21 that give you money back for shopping. And the Walmart app has a savings catcher feature where you take a picture of the barcode or upc at the bottom of your receipt and they search all surrounding store and if a lower price is found they give you the difference back. I have made about 50 bucks total from this app and 20-30 from things like ibotta.
Really great ideas, I’ve started with teaching english to Chinese children a month ago and am really satisfied. I feel that it allows for enough free time and still provides a lot of money for the time and work invested. I am using a different system that you are saying, but will try the one that you recommended. I wanted to go into proofreading, but I feel that my english is not great enough, so I would not do good. Also, I’m not really a person that always sees all the details. So, teaching english, my next lesson is in 6 hours.
In mid-2017, I sold my San Francisco rental property for 30X annual gross rent and reinvested $500,000 of the proceeds in real estate crowdfunding. I’m leveraging technology to invest in lower valuation properties with higher net rental yields in the heartland of America. With the new tax policy starting in 2018 capping state income and property tax deductions to $10,000 and limiting interest deduction on mortgages of only $750,000 from $1,000,000, expensive coastal city real estate markets should soften at the expense of non-coastal city real estate.
In that regard, I highly recommend you build your own email list. By building an email subscriber list using a service like AWeber, you’re essentially creating a list of people that trust you and want to hear about your affiliate products' recommendations. Check out my free course on how to build your subscriber email list if you want to learn more about it.
I wouldn't think of a high yield savings account as a source of passive income but your savings should be getting something (less like Seinfeld syndication residuals and more like a commercial jingle residuals!). It won't make you rich but it's nice if your baseline, risk-free rate of return on cash is 1% or more. The best high yield savings accounts (or money market accounts) offer higher interest rate and there is absolutely no risk. CIT Bank currently leads the pack with the highest interest rate.
Robo-advisors are diversified investment accounts that are automatically managed by a computer algorithm (as opposed to a human money manager). If you want to invest, but don’t have the money, or don’t want to invest with a money manager, robo-advisors are for you! Robo-advisors make investing easier—and cheaper—so they’re perfect for new investors.