Reasons to allow students to use the windows in the CS lab as dry-erase boards:

1. An easily erasable and reusable surface for brainstorming is very helpful when programming and doing math problems. This is why there are so many whiteboards in software development offices.
2. It encourages team work, which not only creates a better learning environment, but replicates real world conditions.
   
3. There is no need to buy an expensive whiteboard. The only additional cost would be window cleaner, which the school already has.
   
4. Several students already bring their own dry-erase markers and erasers.
   
5. The placement in the room is perfect. There is better lighting than in the corner with the bookshelf. It is visible to everyone, unlike the wall by the printer. There are no desks or computers to obstruct usage, unlike with the announcements board.
   
6. The markers will not damage the glass. (Yes, even permanent marker can be removed if someone makes that mistake)
   

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