Here are the Spanish days of the week and their English equivalents. Notice days of the week are never capitalized and have masculine articles. Days of the week ending in -s do not change when plural. Rather, the article only changes. (el lunes=Monday/los lunes= Mondays). When creating sentences remember when used with the days of the week, the definite article has the special meaning "on." (ex. No trabajo el lunes.
=I don't work on Monday).
Recommended textbook explanations
Expresate!: Spanish 1 Cuaderno de vocabulario y gramatica
1st EditionRinehart, Winston and Holt287 explanations