So far, my 6yr is happy to give a report for each chapter book she reads and each nonfiction or biography I assign as schoolwork. Her 5yr sister has asked to write reports also, so I've "given her permission" to complete one for each book she reads (it doesn't count if someone else reads it aloud to her). Her first report was on Have You Seen My Cat? by Eric Carle, but I'm sure eventually she'll work her way up to The Moffats like her sister.
We keep the reports and blank forms in a 3-ring binder. Since both girls use the same binder for now, they write their name and date at the top. When the binder gets full, perhaps we'll turn the sheets into books bound with yarn and store away with similar books they have made for school. They'll have a list of books they read to look back on when they're grown, and a memory maker to see the progress they make year after year.
Linked with Encourage One Another Wednesday and Works for me Wednesday and DIY Linky