When Should A Word Be Written Using Only Kana?

[mikeplusplus]

I'm working with Erin's Challenge right now, and when I look up the words they use in the skits, I find that some of the words they have written in kana have kanji, and it is not specified that the word is supposed to be written using kana alone. Are words like these normally written using kana or kanji?  

[CynHimawari2828]

Maybe it's based on your current level of the language? I have some books that teach kanji, but only use the kanji that is being currently shown/you have to learn (ex. the page shows the kanji for "what"= 何/ なん , and that is the only kanji mentioned in that page).
Then again, I personally have not used the site a lot myself to know for sure. xp  

[Anton Anagram]

There are certain words that will be written in kana to convey a meaning different from the one that would be conveyed if they were written in kanji.

I watched the very last one and I get what you mean.

For example:

和すれない (to not forget or "don't forget" [informal])

can be written as

わすれない

if the speaker feels a more personal relationship to the listener/s.
In this case, classmates with whom Erin had grown attached.

Putting everything into kanji can make your writing more formal and it keeps the listener/s at arm's length.

It is difficult to judge precisely when a word should be written in kana versus kanji but just remember:

The more kanji, the more formal it sounds.

Hope this helped you at all~