As I use Rosetta Stone to learn Japanese, I only use the Kanji mode (except when I forget the reading for a kanji and then flip it briefly to furigana mode). However, I've found that for some reason there are many words that Rosetta Stone seems to arbitrarily choose to use hiragana instead of kanji.
Examples:
ぼく instead of 僕
こわれる instead of 壊れる
かさ instead of 傘
はしご instead of 梯子
and many more.
Is this due to the kanji being to complex accoring to Rosetta Stone or is this a situation where hiragana is typically used instead of kanji? From what I've been able to find in online dictionaries, these aren't flagged as "typically written as hiragana". Since we're reading these words and not writing these words, I would have expected them to favor the kanji forms.
What further seems to confuse me is when reading manga, I've seen 僕, ぼく, and ボク used.