No, they are uncountable nouns.
If we want to count them we have to say 'two pieces of homework' or 'two items/pieces of mail', for example. We wouldn't say two homeworks or two mails.
AbilIf I haven't gotten much mails at my mail box, but I have gotten many letters and many emails from my friends.Is that correct?
Do NOT make mail into "mails."
Whether e-mail is countable or not is still evolving.