I am working at an elementary school as an afterschool activity teacher.

Every April we experience a personanel change.

Another option: Every April we get new staff.

To my surprise, she had a headset microphone while she spoke to children.

This is correct, but another option: To my surprise, she used a headset microphone with her kids.

Especially, during gather and line-up time.

Before weclass start studying, we let thems, the students stand up, psay "attention," do a customary bow, and then take atheir seats.

This is a routine of students of Japan.

This is a ritual for the students of Japan.

ItYou must need to say athe word very louderly.

In my case, I originnaturally have a clear and loud voice.

She said she had been housewife for 30 years because her husband was an airplane engineer who earned a lot of money.

During those years, she didn’t use her voice so much since she didn’t have a partner to talk each other whento after her kids grew up.

So she had no choice but to buy thea headset microphone.

After a while, she got used to her work, and fortunately her voice came back.

I never have thought that the vocal cold is ones are part of a muscle.

If we don’t use anyour muscles, it would be weakethey can easily weaken.

What I learned from this, there is nothing wasted our parts of body even only one thing.

Did you mean "learned" or "gleaned" ? ^^

I am working at an elementary school as an afterschool activity teacher.

To my surprise, she haused a headset microphone while she spoke to children.

Especially, during gather and line-up time.

It mustYou need to say a wordpeak very louderly.

She said she had been a housewife for 30 years because her husband was an airplane engineer who earned a lot of money.

During those years, she didn’t use her voice so much since she didn’t have a partner to talk each othernyone at home to talk to when her kids grew up.

However, she started to work due to thebecause she got divorced.

I never would have thought that the vocal colrd is onea kind of a muscle.

Muscles need to be trained.

If we don’t use any muscles, it would be weakens easily.

But the event was not a bad thing for her but rather good thing.

What I leaned from this, was that there is nothn't a single wasted our parts of body even only one thingour bodies.

I am working at an elementary school as an after school activity teacher.

Every April, we experience a personal change.

To my surprise, she haused a headset microphone while she spoke toen speaking to the children.

We always have to speak loudly forbecause kids can be noisy kids.

Especially, during gather and line-up timthe time where students have to gather and get in line.

Before we start studying, we let themeach lesson begins, students are instructed to stand up, pay attention, bow, then take a seat.

This is a routine ofcustom for students of Japan.

It mustDuring this time, every instruction needs to say a word verybe said louderly.

In my case, I originnaturally have a clear and loud voice.

She said she had been housewife for 30 years because her husband was an airplane engineer who earned a lot of money.

During those years, she didn’t use her voice so much since she didn’t have a partner to talk each otherto when her kids grewwere growing up.

Eventually, ther vocal cords started shrinking day by day.

However, she started to work due to tafter her divorce.

After a while, she got used to the work, and fortunately her voice came back.

I never have thought that the vocal colrd is ona type of a muscle.

If we don’t use anythe muscles, it would be weaken easily.

But the eventdivorce was not bad thing for her but, and instead was a rather good thing.

What I leaned from this, there is nothing wasted our is that every parts of our body even only one thingis important.

I am working at an elementary school as an afterschool activity teacher.

Every April we experience a personal change.

Do you maybe mean 'personnel', meaning 'staff'?

To my surprise, she had a headset microphone while she spokefor speaking to children.

Especially, during gather and line-up time.

No comma needed here :)

Before we start studying, we lethave them stand up, pay attention, bow, then take a seat.

She said she had been housewife for 30 years because her husband was an airplane engineer who earned a lot of money.

However, she started to work due to ther divorce.

I never have thought that vocal cold is onrds are a type of a muscle.

You can also say 'I had never considered..', which sounds more natural!

Muscles need to be trained.

If we don’t use any muscles, it would bethey weaken easily.

The vocal cords are the same.

What I leaned from this, there is nothing wasted our is that not even one parts of our body even only one thingis a waste.