Sure, here are ten sentences that can be used to write a letter in English for a fifth grader:
1. Dear [Recipient's Name],
3. I wanted to update you on something fun that happened to me recently.
4. I really enjoy [hobby/activity], and I wanted to share some of my experiences with you.
6. I'm currently learning about [subject], and I thought you might be interested in some of the things we're covering.
7. I'm looking forward to [upcoming event], and I was wondering if you would like to come with me.
8. I have a new pet at home, and I wanted to show you a picture.