Formula for How Many Computer Labs at a School (Updated)


At a time when most folks might want to abandon computer labs in a school district for mobile devices, carts, etc., a sad fact stands in the way. The fact is that high stakes testing is currently best achieved in a traditional computer lab setting.

Although iPads, Chromebooks are the way of the future, that 3 to 1 devices overshadow the old 1 to 1 concept, the fact remains that high stakes testing impedes future implementation of this vision of highly mobile devices eliminating computer labs. It is ironic that while we advocate for mobile device enhanced learning, in the end, it is high stakes assessments required by the State that consume most of the funding available to schools. Simply high stakes testing relies on old technology that isn't mobile, may be more expensive to maintain and implement.

The situation was predicted by a colleague of mine years ago. In the end, there will be time for only one sort of activity in our schools' computer labs. The work of test prep, drill-n-kill, tutorial, and assessment. As a committed instructional technologist, I am committed to keeping educational technology alive. As an administrator, I find myself planning for computer labs.

So, in that spirit of number crunching, what's the formula for how many computer labs need to be implemented in a school with how many computers per lab?

I see this as a math problem, and math isn't my strongest subject. If you know a better way, I humbly ask for your insights.

Here are the questions:

  1. In an elementary school with 500 students, how many labs and computers per lab should there be?
  2. In a middle school with a total enrollment of 1,200 students, how many labs and computers per lab should there be?
  3. In a high school with a total enrollment of 2800 students, how many labs and computer per lab should there be at minimum?

Some points to keep in mind:

  • The ratio of students to computers for purposes of a lab is 11 students to 1 computer.  I read this somewhere and don't have a source (late night desperation searches months ago and I failed to bookmark the PDF)
  • In my State, 22 students is the maximum possible size of a classroom in elementary grades.
  • Middle and High School classes can have 30+ students in them but for purposes of this conversation, I'm going to impose a limit of 30 students as max class size.

Formulas to Get Desired Information:

  • To obtain the Total Lab Computers that need to be purchased, divide Total Enrollment by student:computer lab ratio of 11.
  • To obtain the Total Number of Labs, divide the Total Lab Computers by your total max class size.

Applying the Formula:

In an elementary school with 500 students, how many labs and computers per lab should there be?
  1. Total Lab Computers = 500/11 (Result: 45 computers for labs)
  2. Total Number of Labs = 45/30 (Result: 1.5 labs)
Here's what that looks like with real numbers...note that the columns titled Projected Labs and and Projected Computers are the results of the formula above.

The projected data is used to calculate how much equipment needs to be purchased to replace the obsolete equipment.

My final question is as follows: Is this reasonable or is there a major flaw in my calculations?

Update: In response to this blog entry, Doug "Blue Skunk" Johnson wrote the following:

Hi Miguel,
For some reason, you blog doesn't seem to want me to leave a comment. Feel free to add this reply to your blog if so inclined. 
You have to think about "how many labs" when it comes to testing. First, any lab used for testing  needs to have as many machines as your building's largest class plus 2 (if it is high-stakes testing). You may also want some mini-labs scattered about the school for testing special needs students, make up tests, etc. 
Then you look at the testing window - how many days you will have to give the test. Next you look at the length of the test and determine how many classes can be scheduled to take the test per day. That will determine how many labs you need. 
For example, if you have a 10 (school) day window and you can test 4 classes a day, one lab can accomodate 40 classes of students. Make sense?
We've been doing online testing here in MN for a number of years. It's a pain in the ass and a terrible waste of computer resources - hardware, bandwidth, and tech support. But it also provides a rationale for reliable computers, sufficient internet capacity and adequate tech support. And job security for all the wrong reasons. 
Good luck and let me know if you have questions,
Doug Johnson
Web: www.doug-johnson.comBlue Skunk Blog: blueskunkblog

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Scott McLeod said…
Can I vote that whatever formula you use, the answer should be zero? (because every kid should have his or her own computer instead)

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