Tim's homework:

When I went to Euroupe it was really fun. I went to Italy,france.swiss and, Germany. I saw Eiffle tower,jungfrau and more famous places. It was alot of fun.
After I went to Europe I hade really hard jetleg for 2 days.

Tim:  I went to Italy,france.swiss and, Germany. I saw Eiffle tower,jungfrau and more famous places.
Correct:  I went to Italy, France, Swiss and, Germany. I saw the Eiffle tower and jungfrau as well. I've actually seen many famous places in Europe.
Explanation: Proper nouns should always be capitalized.

Tim: When I went to Euroupe it was really fun.
Correct: When I went to Euroupe, it was really fun.
Explanation: Comma is a mark (,) used to separate parts of a sentence. 

Tim: After I went to Europe I hade really hard jetleg for 2 days.
Correct: After I went to Europe, I really had a hard jet lag for two days.
Explanation: Be careful with some of your spellings. Also, remember numbers from 1-10 should always be spelled out when writing a composition.

Tim: It was alot of fun.
Correct: It was a lot of fun.
Explanation: It should be separated.

Comments:
Hi tim! It seems like you you'll treasure a lot of happy memories you had in Europe for the rest of your life. Anyway, you did a great job in this homework, thank you for sending me this homework on time.  Just remember my corrections in here and I'll see you on Monday, Tim and have a great weekend! Good night! :)
-Teacher Dianne