Which words do Canadians spell differently than Americans?

There are actually a large but finite number, where the spelling in the US developed through separate US dictionaries. Sometimes the British spellings are acceptable variants in the US. They include, but are not limited to:

or/our Words : color-colour, honor-honour, neighbor-neighbour
e/ae Words : hemophilia-haemophilia, encyclopedia-encyclopaedia, esopaghus-oesophagus
ce/se Words : license-licence,
er/re Words: center-centre, fiber-fibre
z/s verbs : analyzed/analysed, criticize/criticise
Y Words : pajamas-pyjamas, tyre-tire
dropped UE Words: analog-analogue, catalog-catalogue
doubled consonants : canceled-cancelled, traveled-travelled
shortened Words: jewelry-jewellery, story-storey

(also see the related link)