"My dog is eating my homework!"
Translation:Hunden min spiser leksene mine!
In Norwegian you will talk about lekser in both singular and plural, all depending... To have "Hunden min spiser leksa mi" feel right, it would have to be that your dog actually picks one of your items and eat it, like if he takes the one you are working with and tears it from your hands. Homework is uncountable, translating it into plural in Norwegian is both correct and natural.
Har du gjort lekser? Gjør leksene først. Jeg skjønner ikke denne leksa. Dette blir i lekse til i morra. (Did you do your homework? Do your homework first. I don't understand this homework. This is homework for tomorrow.)