Are 1942 copper pennies worth a lot?

Answer 1

Threepences were not made from copper.

British 1962 Threepences were made from nickel-brass.

The 1962 Threepences issued by most other British Empire/Commonwealth countries were either partly silver or cupro-nickel, but all with a silver appearance.

Modified coins have no collector value.

Answer 2

Copper is the normal metal for 1942 copper cents (1943 cents are the ones where the copper ones are worth thousands of dollars) and they are only worth about 3 cents. They are fairly common and not worth all that much.