Worms with shells???

Question

I found a wierd worm with a shell in my house. I thought it was a piece of woodbark until it moved. It looks like there's a little worm living inside of the shell. The shells are less than 1cm long and are beige/brown/gray in color. The shell is shaped like a football with narrow ends and a wider middle. There are two small openings on both ends. The head sticks out of both (not at the same time) ends and pulls the shell up to move around. Does anyone know what this is?

Answer 1

Nice Observations.

It is called as the Caddis Worm (Also spelt as Caddice Worm). Caddis fly adults resemble small moths, and like moths, are attracted to night lights. The larvae, caddis worms, form small portable protective cases out of leaves, sticks, sand, or anything else available. They grow within these artificial shells and emerge as an adult. They live in water (sometimes can be seen crawling up the walls) and grow to be a fly after sheddng their temporary protection.

Check sources for image and life cycles.

Answer 2

It's probably some type of mollusk or insect larva; worms don't have shells.