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Every lesson on Studyfern, by subject, in the order they build.
Finance 41 lessons
- Compound interest 5 min
Interest that earns interest, and why the years matter more than the rate looks.
- Present value 5 min
How to compare money paid at different times.
- Measuring inflation with a price index 4 min
How a basket of shopping turns into one inflation number.
- Real and nominal interest rates 3 min
What your savings really earn once rising prices are counted.
- Costs and the market return 3 min
Why investors as a group must earn the market return minus their costs.
- The Gotrocks family 4 min
Bogle's parable of a family that owned every company, until the Helpers arrived.
- Where stock returns come from 5 min
Dividends, earnings growth, and the swing in what investors will pay: Bogle's way of splitting the market's return.
- Owning the whole market 4 min
Index funds, the S&P 500 and total-market indexes, and why a market-value-weighted index looks after itself.
- Fund returns versus investor returns 6 min
Why the return a fund reports is not the return its investors actually get, and how timing opens the gap.
- Taxes are costs too 5 min
How trading inside a fund creates tax bills, and why Bogle counts taxes alongside fees.
- When future returns are lower 5 min
Bogle's 2007 forecast, built from dividends, growth and the P/E ratio, and what actually happened next.
- Why past winners rarely repeat 5 min
Survivorship, reversion to the mean, and star ratings: why picking yesterday's best fund is harder than it looks.
- Paying for advice 5 min
What a financial adviser can and can't do for you, how advisers are paid, and what an advice fee costs over time.
- Costs go on forever 5 min
Expense ratios, sales charges and trading costs, and why low cost is the most reliable guide Bogle found.
- Bonds and money-market funds 4 min
When returns come almost entirely from interest, costs take an even bigger bite.
- New indexes and ETFs 5 min
"Smart" indexes that promise to beat the market, and exchange-traded funds: Bogle's doubts, and the case for them.
- Graham, the arithmetic, and a plan 5 min
Benjamin Graham's defensive investor, Bogle's "relentless rules of humble arithmetic", and the plan he suggests: one investor's reasoned view.
- Investment versus speculation 4 min
Benjamin Graham's test for what counts as investing, and his two kinds of investor.
- Inflation and the investor 4 min
Why neither bonds nor stocks fully protect you from rising prices, in Graham's data and Zweig's.
- A century of market history 5 min
How Graham judged whether the whole market was cheap or dear, and why he never trusted the past to repeat.
- The defensive investor's portfolio 4 min
Graham's split between bonds and stocks, the 50–50 default, and rebalancing when the mix drifts.
- Defensive investors and stocks 4 min
Graham's four rules for a defensive stock list, why he kept out growth stocks, and dollar-cost averaging.
- What the enterprising investor avoids 4 min
Graham's "don'ts": second-grade bonds and preferreds, foreign government bonds, and new issues sold on enthusiasm.
- What the enterprising investor does 5 min
Unpopular large companies, bargain issues priced below their working capital, special situations, and looking abroad.
- Mr. Market 5 min
Graham's moody business partner who quotes a price every day, and why you don't have to take it.
- Living with fluctuations 5 min
Why even safe bonds swing in price, the shareholder's two positions, and Zweig's list of what you can control.
- Investing in funds 5 min
What Graham thought funds did well, his arithmetic on closed-end funds at a discount, and Zweig's checklist for choosing one.
- The investor and his advisers 4 min
Graham's test for whose advice to trust, what good advisers actually do, and Zweig's "trust, then verify".
- Security analysis for the lay investor 4 min
How Graham tested a bond's safety, his simple growth-stock formula, and Zweig's warning signs in a company's reports.
- Per-share earnings and their traps 4 min
Graham's two warnings about earnings per share: don't trust one year, and read the footnotes.
- Comparing four companies 4 min
Graham's side-by-side method: profitability, stability, growth, finances, dividends and price, on his 1970 four.
- The defensive investor's screen 4 min
Graham's seven tests for a defensive investor's stocks, from financial strength to the 22.5 rule, with a calculator.
- The enterprising investor's screen 7 min
Graham's looser tests for an enterprising investor, what his single-factor experiments found, and the advice to practise on paper first.
- Convertibles and warrants 6 min
How a convertible bond works, why Graham mistrusted new ones and condemned warrants, and Zweig's view of convertibles today.
- Four extreme case histories 7 min
Graham's four cautionary tales from 1968–1971, the warning signs each one showed, and Zweig's parallels from the dot-com years.
- Eight pairs of companies 7 min
Graham's method of comparing neighbouring companies on price, quality and record, with two of his pairs and one of Zweig's.
- Shareholders, managements and dividends 5 min
Graham on what owners should expect of managers and dividends, and Zweig on proxy statements, buybacks and executive pay.
- Margin of safety (1): the idea 5 min
Graham's central idea, the gap between price and value that protects you from error, for bonds, ordinary stocks, growth stocks and bargains, with a calculator.
- Margin of safety (2): in practice 7 min
Why a margin of safety needs diversification, how Graham used it to tell investment from speculation, his four business principles, and Zweig on the cost of a big loss.
- The superinvestors of Graham-and-Doddsville 6 min
Buffett's 1984 argument that Graham's followers beat the market by skill, not luck, and the reasons to weigh it with care.
- Graham today 7 min
Graham's postscript on one lucky, well-prepared decision, Zweig's closing advice, and a review of the whole path.
Psychology 6 lessons
- Test yourself instead of rereading 3 min
Pulling an answer out of your memory makes it stick far better than reading it again.
- Space it out 3 min
Short reviews spread over days beat one long cram.
- Mix your practice 3 min
Shuffling different kinds of problems feels harder, and teaches more.
- Focus in short sessions 3 min
Work in focused blocks with real breaks, and put the phone in another room.
- Make a study plan you will keep 4 min
Decide when, where and what, in one "if–then" sentence.
- Practising speaking with an AI 5 min
Set up any voice-capable AI assistant as a patient tutor, ask it for useful corrections, and know when not to trust it.
Latin 62 lessons
- Saying Latin out loud 4 min
Hard c, v like w, and where the stress falls.
- Endings do the work 3 min
In Latin, the ending of a word shows its job, not its place in the sentence.
- The five cases 3 min
Nominative, genitive, dative, accusative, ablative: five jobs a noun can do.
- The first declension 3 min
All ten forms of puella, and which -a nouns are masculine.
- Adjectives agree with their nouns 3 min
bona puella, nauta bonus: the adjective matches the noun's gender, number and case.
- The second declension 4 min
dominus and pīlum: masculine -us nouns and neuter -um nouns.
- Predicate nouns and apposition 3 min
When two nouns name the same person, they share the same case.
- Adjectives in all three genders 3 min
bonus, bona, bonum: one adjective, three sets of endings.
- Nouns in -ius, -er and -ir 4 min
fīlius, puer, ager, vir: second-declension nouns with a twist.
- My, your, his, our 3 min
meus, tuus, suus, noster, vester: possessives that agree with the thing owned.
- Four ways to say "with" 3 min
The ablative of cause, means, accompaniment and manner, and when to use cum.
- The nine irregular adjectives 4 min
ūnus, nūllus, sōlus, tōtus and friends: genitive -īus, dative -ī.
- is, ea, id: this, that, he, she, it 3 min
One word for "this" and "that", which also stands in for he, she and it.
- sum: I am, I was, I shall be 3 min
The verb "to be" in the present, imperfect and future.
- The present of amō and moneō 4 min
The first two conjugations, and how the infinitive tells you which is which.
- The imperfect: was doing 4 min
The tense sign -bā- for actions going on in the past.
- The future: will do 3 min
The tense sign -bi- for the first two conjugations.
- The dative with adjectives 3 min
"Friendly to", "pleasing to", "near to": adjectives that take the dative.
- The present of regō and audiō 4 min
The third and fourth conjugations, and the vowel that changes.
- The imperfect of regō and audiō, and verbs that take the dative 3 min
regēbam, audiēbam; and why "obey" and "believe" take the dative.
- The future of regō and audiō 3 min
regam, regēs, reget: a new tense sign, and a look-alike trap.
- capiō, and giving orders 3 min
-iō verbs of the third conjugation, and the imperative: amā! audīte!
- The passive: being done to 3 min
amor, amāris, amātur: the passive endings for the first two conjugations.
- The passive of regō, audiō and capiō; passive infinitives 3 min
regor, regeris, regitur; regī, "to be ruled".
- Synopses, and the ablative of "from" 3 min
Place from which, separation, and "by" a person with the passive.
- fuī, fueram, fuerō: the perfect tenses of sum 3 min
Principal parts, the perfect stem, and three tenses of completed action.
- The perfect active: did, have done 5 min
amāvī, monuī, rēxī, cēpī, audīvī, and when to use the perfect or the imperfect.
- Had done, will have done: pluperfect and future perfect active 3 min
amāveram, amāverō, and the perfect infinitive amāvisse.
- amātus sum: the perfect passive 4 min
The perfect passive participle, and passive perfects made with sum.
- Principal parts, prepositions, and yes-or-no questions 5 min
Four parts for every verb, which case each preposition takes, and -ne, nōnne, num.
- possum, "I can", and the infinitive 3 min
possum, potes, potest; the infinitive that completes a verb, takes a subject, or acts as a noun.
- quī, quae, quod: who, which, that 4 min
The relative pronoun, its agreement rule, and the question words quis and quid.
- rēx, rēgis: the third declension 4 min
Consonant stems, the genitive that holds the key, and the endings -is, -ī, -em, -e.
- hostis, urbs, mare: i-stems 4 min
Third-declension nouns with -ium in the genitive plural, and neuters with -ī and -ia.
- vīs and iter; gender in the third declension 4 min
Two irregular nouns, and rules of thumb for telling masculine, feminine and neuter.
- omnis, ācer, pār: third-declension adjectives 3 min
Adjectives of three, two and one ending, all with -ī in the ablative.
- manus, cornū: the fourth declension 3 min
Nouns in -us with a genitive in -ūs, and neuters in -ū.
- Rōmae, domī, Athēnīs: place and the locative 4 min
To, from and in a place, and why towns, home and the country drop the preposition.
- diēs, rēs: the fifth declension and the ablative of time 3 min
The last declension, and how Latin says "on that day" and "in summer" with no preposition.
- ego, tū, sē: personal and reflexive pronouns 4 min
I, you, we; "himself" and "themselves"; and mēcum, "with me".
- ipse, "himself", and īdem, "the same" 3 min
The intensive pronoun and the demonstrative īdem, eadem, idem.
- hic, iste, ille: this and that 4 min
Three demonstratives that point near me, near you, and over there.
- aliquis, quīdam, quisque: someone, a certain, each 3 min
The indefinite pronouns, built from quis and quī.
- clārior, clārissimus: comparing adjectives 4 min
-ior and -issimus, the -er and -lis exceptions, and quam or the ablative for "than".
- melior, optimus: irregular comparison, plūs, and "by how much" 3 min
good–better–best in Latin, plūs, and the ablative of the measure of difference.
- clārē, fortiter: adverbs and their comparison 4 min
Making adverbs from adjectives, comparing them, and the irregular bene, melius, optimē.
- ūnus, duo, trēs: numerals, "of" the whole, and "for how long" 5 min
Counting to twenty, the partitive genitive, and the accusative of extent.
- hortor, sequor: deponent verbs 3 min
Verbs with passive forms and active meanings.
- amem, regam, sim: the present subjunctive 4 min
A new mood for wishes, commands to ourselves and ideas rather than facts.
- ut, nē, quī: purpose clauses 3 min
"In order to" in Latin prose is never an infinitive. It is usually ut (or nē) with the subjunctive.
- amārem, essem: the imperfect subjunctive and the sequence of tenses 4 min
The infinitive plus endings, and how the main verb picks the tense of the subjunctive.
- amāverim, amāvissem; indirect commands 3 min
The perfect and pluperfect subjunctive, and "he urged them to …" with ut or nē.
- possim; "I fear that …" 3 min
The subjunctive of possum, and why nē means "that" after a verb of fearing.
- amāns, amātus, amātūrus, amandus: participles 3 min
Four participles, what time each shows, and how to turn them into good English.
- volō, nōlō, mālō; the ablative absolute 4 min
Wish, be unwilling, prefer; and "with Caesar leading", Latin's favourite compact clause.
- fīō; "so … that": result clauses 4 min
The passive of faciō, and ut / ut nōn with the subjunctive for consequences.
- "The man to lead us": clauses of characteristic 3 min
Relative clauses with the subjunctive that describe what kind of person or thing, and the predicate accusative.
- cum: when, since, although 3 min
The three meanings of the conjunction cum, which mood follows, and the ablative of specification.
- amandī, ad urbem videndam: gerund and gerundive 4 min
The verbal noun "-ing" and its adjective partner, purpose with ad or causā, and the predicate genitive.
- eō; "he said that …": indirect statement 4 min
The verb "go", and how Latin reports what someone says or thinks with an accusative and infinitive.
- ferō; the dative with compounds; indirect questions 4 min
The irregular verb "carry", compounds that take the dative, and "he asked who …" with the subjunctive.
- The cases and the moods: a review 4 min
The dative of purpose, description by genitive or ablative, and every use of the cases and the subjunctive in one place.
Learning paths
- How to study
5 lessons · about 16 min
Five research-backed habits that make any subject easier: test yourself, space it out, mix your practice, focus in short sessions, and make a plan you will keep.
- Studying in the age of AI
1 lesson · about 5 min
Using your own AI assistant as a study partner, honestly: what it is good for, and where to check it.
- Money over time
5 lessons · about 20 min
How money grows, what it is worth today, what inflation takes, and what costs take.
- Common-sense investing: the case for index funds
13 lessons · about 61 min
John Bogle's argument for owning the whole market at low cost, taught chapter by chapter from The Little Book of Common Sense Investing, with the arithmetic worked out and his 2007 figures clearly dated. Education only: no fund recommendations.
- The Intelligent Investor: Benjamin Graham's ideas
24 lessons · about 122 min
Benjamin Graham's classic, taught chapter by chapter with Jason Zweig's commentary: investing versus speculating, the defensive and enterprising investor, Mr. Market, reading a company, and the margin of safety. Graham's companies and figures are taught as dated case studies. Education only: no stock tips.
- Latin Level 1: nouns and cases
13 lessons · about 43 min
From the sounds of Latin to the first two declensions, adjectives, possessives, the ablative of "with" and is, ea, id. Ends with the Basics self-test.
- Latin Level 2: verbs and the other declensions
35 lessons · about 124 min
sum and the four conjugations in the present, imperfect and future, then the passive, the perfect tenses and the remaining declensions. Ends with the Intermediate self-test.
- Latin Level 3: constructions
14 lessons · about 50 min
The subjunctive and the great constructions: purpose, result, indirect commands, fearing, participles and the ablative absolute, cum clauses, gerunds, and reported speech and questions. Ends with the Advanced self-test.