What is the best layout for a Middle School computer lab? My school director has given me the opportunity to redesign the layout of our school's IT lab to better suit my classes.  Currently the computers are in the "inverted U" layout listed here so that I can monitor students' monitors but not their faces.

I find that this makes classroom management difficult (I teach grades 6-9).  Students frequently get distracted by what is on their neighbors' computers, and every student can see every other student's monitor without much effort.  It also makes individual work like quizzes/exams basically impossible.  If I have to make an announcement I am making it to the backs of students' heads.  Students have to turn their whole chairs around (we don't have office chairs) to pay attention to a lesson, which means they can't comfortably take notes on what I am saying or what I write on the board.

I'm currently debating with myself between three layouts:


computers in clusters of four (the four-leaf clover layout from the link above)
computers in rows such that students face the front of the room and monitors face the back, like this (I would then teach from the front, and when students had work time I would move to the back to monitor the screens)
computers in four rows: one row against each side wall (students facing the walls), two rows together in a center island (students facing each other), such that I would have an oblique view of the monitors from the front of the room and students would have to rotate about 90 degrees to face forward.
The features that should guide your classroom layout are visibility, accessibility, and distractibility — maximizing the first two, and minimizing the third.

Visibility is simple: every student should be able to face forward easily with unobstructed view, and I should be able to see every student's face.

Accessibility, here, means that I should be able to get to every student quickly, and that students should be able to work with each other when I assign pair-programming tasks or ask them to discuss a question with neighbors.

Those first two considerations already rule out front- or rear-facing rows, and some cluster arrangements as well.

Regarding distractibility: From years of teaching and observing other teachers, I take as an axiom that lecturing to students who are looking at computer screens is an effectively pure waste of time. This has corollaries:


Screens should be less than about 120° from facing the front of the room — ruling out rear-facing screens.
Lectures should be short and focused.


At this point I should give some context about my classes:


The first cue I teach the students is "screens off!", and I say this whenever I need to address the class as a whole. (If I'm interrupting work, I first give an advance warning so they can find a stopping point and save their work.)
I ask students to bring a notepad and writing tools, for drawing or taking notes while their monitor is off.
I aim to limit lecture time to ten-minute chunks at most, punctuated with pair discussions.


Because I have the students turn off their monitors, my lectures must require either no handwritten note-taking, or minimal note-taking (which then requires me to give some explicit instruction on how to take notes).

Now, I have taught in labs with traditional rows (students facing forward, monitors back), clusters, and variations on the "inverted U" design you're talking about. Currently my lab is set up with student workstations all along the left and right walls, so that students are all facing the wall while working, and the computers are all facing inwards — very much like the last option you described, only without a central island (because the room is too small for one). This is my preferred layout.

So, I would endorse the last option you suggested, of computers along the side walls, with an optional cluster of side-facing machines in the center of the room.