"The Standards for Mathematical Practice describe varieties of expertise that mathematics educators at all levels should seek to develop in their students. These practices rest on important “processes and proficiencies” with longstanding importance in mathematics education..."
The Mathematical Practices transcend grade level standards. They are relevant and can be grown at every stage in a student's education. These habits of mind can be applied outside of a math environment and help promote life long learning.
Link to a great blog post from Scholastic about implementing the 8 Mathematical Practices in your classroom