Yes Costco is a great idea. But not necessarily to buy food. They are famous for a) Having lots of tasting stations and b) never saying anything to customers about how many samples they take. So, for $60 you can eat for otherwise free for the rest of your life. The never check the dates on the cards you flash to them, so while after a year you will no longer be able to buy anything you can still eat. Also, Costco lets anyone use their pharmacy so you could get in just by telling them you have a prescription, if the $60 is too much.
I am going to chime in with a source for additional lists- long distance hikers such as for the AT (appalachian trail) as well as for the PCT (pacific crest trail). Many of them do it on an extremely tight budget, shopping almost exclusively at WalMarts and their ilk, eating 5-6,000 calories per day, and maintaining incredible fitness and stamina. Poptarts are a sign of someone additiaonlly who doesn’t like to even cook their food and still live on such a diet. $5/day or at least well under $10 even on that calorie count is not impossible. One hiker recently ate exclusively from the McDonald’s dollar menu for 2 or 3 weeks that I saw. He purchased 60 chicken nuggets for one week and 60 hamburgers the next, both stayed fresh the entire week!
Googling AT on a budget will get you started. AT is probably better guide as there is more food stops and options along the way so easier to be super cheap.
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Now that this has spent a fair amount of time in GQ, let’s move it over to Cafe Society so our resident foodies can give their perspective.
How do you fit 60 hamburgers into your backpack? Also, those macdonald’s dollar menu hamburgers are kind of gross when they are fresh, after it’s been a week and the thing has been stuffed into a bag…eww…
That took a whole lot longer than I’d expect.
Yes Costco is a great idea. But not necessarily to buy food. They are famous for a) Having lots of tasting stations and b) never saying anything to customers about how many samples they take. So, for $60 you can eat for otherwise free for the rest of your life. The never check the dates on the cards you flash to them, so while after a year you will no longer be able to buy anything you can still eat. Also, Costco lets anyone use their pharmacy so you could get in just by telling them you have a prescription, if the $60 is too much.
As somebody with Chaco in their name, you could have made a much more unappealing recommendation. 
On the bulk foods, Ya gotta check and compare those prices. Not very often, but once in a while, the price for the bulk is the same and once even higher than the packaged foods.
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You generally build up a clientele of English students through word of mouth, either adults speaking to each other or the parents of kids. To start with you’ll probably be better off giving discounts for the first few lessons, if they return try to get your students to buy a batch - if they pay for each lesson individually they’re more likely to skip lessons, meaning that hour you’ve reserved for them is wasted and also they lose momentum.
As to the teaching, it can take many forms. Some students will need specific help with grammar or essay writing, others will just want to chat, some will only be there because of peer or parental pressure. Finding out how they’ll benefit should be your primary concern and give the first few hours to drilling down into what their needs are and how they feel most comfortable, speaking to you over Skype. Don’t be offended or hurt if more than 50% don’t choose to have a second lesson, many students are fickle and lazy, looking for that ‘magical’ teacher where the student doesn’t have to try at all, and can absorb the knowledge through osmosis. You’ll find teaching the long-termers much more rewarding anyway.
A previous go at the challenge to eat a diet nutritionally adequate for the least money possible, bonus for taste and interest.
Yes the go-to is the brown rice/greens (frozen in bulk or fresh on sale, maybe some on sale squash too)/beans (dry) combo with peanut butter a very cost effective staple in the mix and canned tuna a reasonably priced protein variety, chicken bought frozen bulk not too far behind.
Surprising the variety that can be made around those backbones. Spices are likely already a fixed cost in the pantry.
Potatoes only complete if also with a fair amount of milk and some source of molybdenum like oatmeal. The milk needed makes it less cost-effective. But good as part of a value priced mix.
A couple of links below for old discussions about this. My first recommendation: Get a year’s supply of cheap vitamins and take one every day. The “expensive pee” folks will be in to whinge about this idea, but it really does take the stress out of trying to eat on a budget. Then you can then concentrate on getting your carbs, protein, fiber, and the occasional nice flavor; it’s a lot less to worry about.
Best source of breakfast is eggs and oatmeal. They are quick and nutritious and cheap. I find that I feel more satisfied all day if I pack on the protein first thing in the morning, so I never use cereal unless I can afford Kashi.
I’ll copy below some old advice about rice and lentils. Lentils are incredibly nutritious, and a great basic canvas for almost any other flavor. I buy them in bulk at Wegman’s, much cheaper than packaged.
If you live where there’s a feed store, a bag of rolled oats from there will be vanishingly cheap, and give you breakfast for 6-12 months. Just take a second to rinse and pick through for gravel before you cook 'em. The same with a bag of rice, the best prices are usually at the asian markets. Get the 20 pound bag.
Do you have a window you can put a pot under? If so, slice the roots off every onion, celery, or garlic, and the tops off every carrot, and plant them. Within a few months you’ll be able to pick a bit off whenever you need it. Plant some basil seeds and dill or whatever herbs you like. The fresh herbs will work wonders on the otherwise boring food, and you get a year’s supply for 75 cents worth of seeds. (I personally love lemon oregano.) The dollar store has all the basic dried herbs and spices you’ll need, in larger bottles than the expensive ones at the grocery store.
Crock pots are crazy cheap at the second-hand stores, grab one; don’t pay more than $5.
Keep a big ziplock bag in the freezer for broth bits. Anytime you trim ends or leaves off of veg, or peel an onion, or trim the fat off of some meat, put it all in the bag. When you have a chicken carcass or other bones, roast it all a bit with the bones and then throw it in the stock pot. Have a second bag for juice from canned tomatoes, or beans, or from boiling veg for dinner. Keep it all and then reduce it with your stock for extra flavor and nutrition.
If you have a big freezer, use it! Buy three turkeys now while they’re on sale after the holidays. Watch for chickens to go on sale and stock up through the year. Always re-roast the carcass and make soup with it once you’ve picked it clean.
Watch for sales on pasta. Periodically you’ll be able to get it for 50 cents a pound or less. Stock up.
Some old links and a post of mine copied out from back then:
I’m really, really sensitive to most legumes. If they’re mashed into a paste like peanut butter I can tolerate them, but even a few tablespoons of peanut butter (more than you’d need for one PB&J) or refried beans will have me on the toilet for a few hours later on. (And it’s much worse if I eat the beans whole. I love baked beans but…ahem…they do NOT love me. 
)
So–is there any alternative to legumes+rice=whole protein? (Note: this is purely hypothetical and a question I keep meaning to ask but keep forgetting to.)
Dairy has protein. Eggs have protein.
You can get inexpensive cuts of meat, sausage can be cheap (although fatty - but if you’re mainly eating grain and veg otherwise it won’t be such a problem). Purchase cheaper cuts on sale.
How do you feel about tofu?
I Googled “The Second International AcidBase Symposium” and I got exactly one hit. It was a for a review article by Peter Melamed and Felix Melamed. So then I Googled Felix Melamed:
Something tells me that YamatoTwinkie’s links are at least a tad more reliable.
Have you tried Beano? It contains an enzyme that breaks down some of those indigestible sugars that give you the bowel shimmies. And the gas. Or ask your pharmacist for some of the alternate products that do the same thing.
Why would he want an alternative product to give him the bowel shimmies? It sounds like beans already work just fine.