What is something you spent a TON of time preparing, but now you know better? For example, last summer I created my first class syllabus (for HS) and it was six pages long. It took me HOURS and DAYS and didn't even include a calendar of studies -- just procedures, rules, etc. Then I came to school and saw most other teachers had a one page syllabus front and back. Oops. I spent an exorbitant amount of time on it and the kids had to be reminded 39573753458 times what was in it anyway! Another time-waster was typing up all my students' names in a seating chart before the first day of school. I didn't anticipate add-ons, drops, and all other factors that would interfere with the arrangement. Many of my procedures and rules were things I was trying for the first time and didn't know how they would work in my actual room since I'm a first year. What I've learned: never make a rule or procedure you can't enforce or keep up with! So... what are some things you've done this year or over the years that you know better now not to do, or to wait to do?