I believe math journals are the heart and soul for algebra and geometry students. Next year I am thinking of buying my students small journals for the students to write in and journal each day (if I have money). But, I have found many different math journals and different ideas for math journals from Pinterest.
The first is a math journal from Cheri Summers and the second is my pin board.
These different ideas help teachers become good teachers and help students learn in different ways. Visually it helps students see what they are doing and why they are doing it, (which is a big thing).