*corrections

*more natural way of saying it

I'm in Virginia, and today was snowing so my filed trip and afternoon class was canceled!

*I'm in Virginia, and it was snowing today so my field trip and afternoon class was cancelled!

When I was told that my afternoon class and one of tomorrow classes were canceled, I felt great happiness.

*When I was told that my afternoon class and one of the classes tomorrow were cancelled, I felt really happy.

Also today's lunch was good!! It was my day.

Now I'm waiting for a mail, which means class will be canceled.

*Now I'm waiting for the mail that will say the class will be cancelled.

('수업이 취소됐다는 이메일을 기다리고 있어요'라고 말하고 싶은거지요? :) 여기서 "the"는 어떤 내용의 메일인지 뒤에 설명을 하기 때문에 붙이는 거에요~ 특정한 메일이니깐요!)

I'm an exchange student and it was first time that my class is canceled because of snow.

*I'm an exchange student, and it was the first time that my class was/got cancelled because of snow.

I thought why Korean schools were not canceled.

*I thought about why Korean schools were not cancelled.

There are some reasons.

First, usually Jan and Feb are our vacation.

First, usually Jan and Feb are our vacation time.

*First, usually our vacation is in January and February.

Our spring semester starts at March.

*Our spring semester starts in March.

So when we have heavy snow, (It depends on area. I live in Seoul but Gangwondo has heavier snow than Seoul.) the time is already vacation.

*So when we have heavy snow, (It depends on the area.

*the time is already vacation -> it's already vacation.

Second, America is much bigger than Korea. America is a huge country.

So a lot of people use their cars for coming school.

*So a lot of people us their cars to come to school.

and the road is more dangerous

because America's the dense of population is lower than Korea's.

*because America's density of population is lower than Korea's.

*because the density of the population in America is lower than in Korea.

(미국에 사람들이 많아서 차를 많이 타기 때문이라면 lower이 아니라 higher이어야 될 것 같은데, 맞나요?) 

Even though we have snow, the road will be normal. Because the heat of cars melts the snow.

*Even if we have snow, the road will be fine, because the heat of the cars will melt the snow.

Third, Here's snow is more than Seoul!

*Third, here, it snows more than in Seoul!

yes, it is amazing.

Last winter, I saw news and it showed me crazy snow in new york!

*Last winter, I saw the news, and there was a crazy amount of snow in New York!

It reminds me movie "tomorrow" but i think English title is "the day after"or something.

*It reminded me of the movie, "Tomorrow" but I think the English title was "The Day After" or something.

Anyway, I hope tomorrow I can stay in my room safely.

Everyone! please safe driving and walking!

*Please drive and walk safely!

-

Your English is good! Just minor grammar mistakes here and there :) 

Do try to read books/watch tv that will help you pick up more natural English.

I used a bit of Korean to explain things since I knew you spoke Korean! Hope that helped~

Snowing in the U.S

I'm in Virginia, and today was snowing so my filed trip and afternoon class was canceled!
When I was told that my afternoon class and one of tomorrow classes was canceled, I felt great happiness.
Also today's lunch was good!! It was my day. Now I'm waiting for a mail, which means class will be canceled.

I'm an exchange student and it was first time that my class is canceled because of snow.
I thought why Korean schools were not canceled.
There are some reasons.

First, usually Jan and Feb are our vacation. Our spring semester starts at March. So when we have heavy snow,(It depends on area. I live in Seoul but Gangwondo has heavier snow than Seoul.) the time is already vacation.

Second, America is much bigger than Korea.
America is a huge country. So a lot of people use their cars for coming school.
and the road is more dangerous because America's the dense of population is lower than Korea's.
Even though we have snow, the road will be normal. Because the heat of cars melts the snow.

Third, Here's snow is more than Seoul!
yes, it is amazing. Last winter, I saw news and it showed me crazy snow in new york! It reminds me movie "tomorrow" but i think English title is "the day after"or something.

Anyway, I hope tomorrow I can stay in my room safely.

Everyone! please safe driving and walking!