What is Best Practice when storing MacBooks for over a month? We have a pod of 30 MacBooks and MacBook Pros that don't get used over the holidays. 

What's best practice to store the laptops for 6 weeks? I know that when you store laptops for long periods at half charge, unplugged in a cool place is a good idea, but in practice I've just put them plugged-in in the storeroom! Could anyone share their best practice methods when storing these sort of devices?
That's what I think Apple suggests when you need to store you MacBook for longer periods: 


discharge your battery to 50% and keep the laptop in a cool place
if you plan to not use the computer for more than 5 months take the battery off the laptop
you will probably need to charge the battery every 6 months to better preserve it.