I always thought that the words funner and funnest were incorrect, I thought it was "more fun" and "most fun" are they all correct??

It depends on whether you feel 'fun' is an adjective or not.

I had thought 'fun' acting as an adjective (we had a fun time) was for spoken English only, or was a noun + noun combination. In either of those cases, 'funner' and 'funnest' would be incorrect (whatever that means ).

If 'fun' were a noun only, the phrases 'more fun' and 'most fun' would be correct, but wouldn't be used as adjectives; they would be noun phrases, like 'more beer' and 'most beer'.

Merriam-Webster says, however:

"Main Entry: 3fun
Function: adjective
Inflected Form(s): sometimes funner sometimes funnest
Date: circa 1846
1 : providing entertainment, amusement, or enjoyment 'a fun party' 'a fun person to be with'
2 : full of fun 'a fun night' 'have a fun time'"

1846! So 'fun' is an adjective, and 'funner' and 'funnest' do exist. They still sound odd, though.

Thank you!!!