"Caran d'Ache was the pseudonym of the 19th century French satirist and political cartoonist Emmanuel Poiré (November 6, 1858 – February 26, 1909). "Caran d'Ache" comes from the Russian word karandash (карандаш), meaning pencil, which in turn comes from the Turkish words kara taş, meaning black stone." https://en.wikipedia.org/wiki/Caran_d%27Ache
No, it's not an exception. «Ма́льчик» is masculine, so the usual genitive ending is -а (ма́льчик 'boy' — ма́льчика, стол 'table' — стола́) or я after soft consonants (учи́тель 'teacher' — учи́теля).
The ending -и is used for feminine words with stem ending in soft consonant or к/г/х/ш/ж/ч (да́ча 'dacha' — stem is дач- — genitive is дачи). Some masculine words can belong to feminine declension (notably short forms of names, like Ви́тя — stem is Вить- — genitive singular is Ви́ти), those words are exceptions. But «ма́льчик» is not.
No, there are 3 cases in total. :D Russian has 3 declensions:
- feminine a-declenstion (words engling in -а and -я in nominative singular; include some masculine words), e.g., вода́ 'water', во́ля 'freedom', свеча́ 'candle',
- masculine/neuter declension (words ending in consonants and -о or -е in nominative singular), e.g. слон 'elephant', гусь 'goose', яйцо́ 'egg', со́лнце 'sun',
- feminine i-declension (feminine words ending in soft consonant or шь/жь/чь in nominative singular), e.g. рожь 'rye'.
Masculine declension can also end in soft consonant, so it's sometimes difficult to distinguish between a masculine declension and a feminine i-declension.
Native speakers also find this difficult: at school, we paid speacial attention to remembering the correct gender of the words like гусь 'goose (masculine)' and на́дпись 'inscription (feminine)'. Also, they have a different gender in different languages (e.g. in Belarusian), so this suggests they have been a source of confusion for a while.
Also, sometimes words have a declension that is different from its gender. E.g. «па́па» 'dad' has a feminine declension, but it's masculine. Most short forms of names have feminine declension.
Ь (') doesn't make a sound in itself, but it changes the pronounciation of the previous sound. You can try to get this difference by comparing similar words: стол / stol — столь / stol', гол / gol — голь / gol'. I know getting the distiction might be hard, but with some practice you'll understand it.
In fact, in your sentence it changes the meaning! «У мальчика ест карандаш» means '[Something] is eating the boy's pencil'. Creepy!
With «есть» 'there is', you use nominative. With «нет» 'there is no', you use genitive.