Using Writing in Mathematics to Communicate and Make Connections
NCTM Standard: Connections
Instructional programs from prekindergarten through grade 12 should enable all students to-- 
• recognize and use connections among mathematical ideas; 
• understand how mathematical ideas interconnect and build on one another to produce a coherent whole; 
• recognize and apply mathematics in contexts outside of mathematics. 
While mathematics is an integrated field of study, often students view concepts as disjointed chunks of information with little connection or relation. According to NCTM, students from prekindergarten through grade 12 should see and experience the rich interplay among mathematical topics, see and experience this interconnectedness between mathematics and other subjects, and also be able to connect mathematics to their own interests. Viewing mathematics as a whole, such as web of linked concepts, will help students to learn that mathematics is not a set of isolated skills and arbitrary rules. 
How do you place an emphasis on mathematical connections to help students recognize how ideas in different areas are related? Why do you think connections are essential to success in mathematics? Do you encourage students to make mathematical connections through writing?
NCTM Principles and Standards for School Mathematics http://standards.nctm.org/document/chapter3/conn.htm 
NCTM also stress that the opportunity to experience mathematics in context is important. Students should have the opportunity to connect mathematical concepts to their daily lives, as well as to situations from science, the social sciences, medicine, and commerce. Students should recognize the value of mathematics in examining personal and societal issues.
Two general types of connections are important: 
(1) modeling connections between problem situations that may arise in the real world or in disciplines other than mathematics and their mathematical representation(s); and 
(2) mathematical connections between two equivalent representations and between corresponding processes in each.
 
Are there ways you could get students to write about these connections to solidify and articulate their understanding related to connections?
As we can see, the Connections standard is really all about seeing how all of mathematics is really a web of inter-related concepts and skills. These connections are between various elements of content, across courses, and inter-connected to other standards. The Representation standard, the Communication standard, and the Reasoning and Proof standard all are tied to our connections discussion and fundamental in helping students make connections within content as well as out in the “real world”.
The 3 main ideas within the Connections standard really do emphasize the "big picture" when it comes to the idea of mathematics across the curriculum.
• recognize and use connections among mathematical ideas; 
• understand how mathematical ideas interconnect and build on one another to produce a coherent whole; 
• recognize and apply mathematics in contexts outside of mathematics.
Having students value mathematics because they can “see it” around them in other courses and in their everyday lives is probably one of the most valuable pieces of this standard. In addition, helping students to see the relationships between concepts within a course is also very influential for helping students to value mathematics. Making those connections between key concepts is fundamental to cognitive connections and deep learning.
Discussing, writing about, and creating visual representations like concept maps are all ways to help students find connections within mathematics courses.
NCTM Standard: Communication
Instructional programs from pre-kindergarten through grade 12 should enable all students to-- 
• organize and consolidate their mathematical thinking though communication; 
• communicate their mathematical thinking coherently and clearly to peers, teachers, and others; 
• analyze and evaluate the mathematical thinking and strategies of others; 
• use the language of mathematics to express mathematical ideas precisely. 
As we ask students to communicate mathematically, we are asking students to take part in a social activity that requires them to reflect on their learning. Students should frequently be asked to express their mathematical ideas, how they interpret mathematical explanations of others, and to be aware of nuances of mathematical language and notation. A variety of situations should be available to students to demonstrate their abilities to communicate their mathematical thinking including written and oral. As students progress to the secondary level, they encounter more abstract concepts and the need to utilize the formal language of mathematics more frequently. The more often students encounter the need to precisely express mathematical ideas the better they will be at communicating their mathematical thinking. As stated by NCTM, the ability to write about mathematics should be particularly nurtured across the grades.
NCTM Principles and Standards for School Mathematics http://standards.nctm.org/document/chapter3/comm.htm
What are some ways that you ask students to communicate their mathematical thinking? In particular, do you ask students to write about mathematical concepts and connections? Can you think of/work toward integrating an individual assessment and a more social/group assessment in relation to asking students to communicate their mathematical thinking?