The Alexandra lad helped his grandmother, Margaret Wilkinson, of Cromwell, gather the items for the capsule, which will be buried in Central Stories' grounds.
Mrs Wilkinson is a committee member of Alexandra District Museum Inc, which trades as Central Stories.
Kohen made sure photographs of Otago skinks were included in the stainless steel capsule, together with stickers marking the museum's anniversary.
He plans a career as an "aeroplane driver", but thought he would travel back to Alexandra by motorbike in 50 years to help dig up the capsule.
"The idea of this time capsule has been around since Central Stores started, but we thought it would be a good part of our celebrations to commemorate our 50 years.
The capsule will be sealed up and placed in a secret location in the grounds and not touched until the museum's centenary," Mrs Wilkinson said.
The items in the time capsule include a 2009 telephone book, a calendar produced by Central Stories, the book of the museum's first 50 years, brochures, a set of coins, the catalogue from the latest exhibition at Central Stories' art gallery, and photographs of the anniversary celebrations.
The celebrations started on December 3.
