Again, this has a connotation of desire instead of hunger. मेरी माँ को भूख लगी है is better
Not really... unless you are specifically looking for innuendos... it is a natural and acceptable way of showing hunger... ofcourse, your way is also correct - infact, I myself use the two alternatively in daily life.
No, it's completely ok... But I know, where you are coming from. Your version is more polished and polite but for someone who's learning Hindi for the first time... This sentence would do.
your job here was to translate the text... not giving alternatives... first decide are you here to learn a Language or words and phrases... soak it in.. it will come slow and steady.. don't depend on this app download lessons from internet or watching videos will help
Of course not, it's completely fine for someone learning the language for the first time. Trust me.
It is more idiomatic to say, "Bhūkh lagnā". As teachers, you should make sure your students learn idiomatic language. I have never ever heard someone use the adjective to mean everyday hunger, especially not native speakers. Doing that would be an anglicism.