We're working on a card for 3rd grade Spanish teacher-does this:
Estimada Sra. Winnette,
Clase de espanola piedras! Espero que usted tenga un verano agradable!
translate to :
Dear Mrs. Winnette,
Spanish class rocks! Have a nice summer!
Thanks for any assistance!
"Piedras" is just a noun, like "stones", or "rubbles"; whoever reads it would be wondering what does a piece of mineral (a rock) has to do with a class, since Spanish does not have a slang like that to mean "it is great". My suggestion:
Estimada Sra. Winette: (you must use colon, not comma)
Las clases de español son geniales. Espero que tenga un verano agradable.
Do not say "usted" here.