Laminators for schools share two characteristics — they must be inexpensive and they must be very safe and easy to use. They will vary in capabilities, since (for instance) a kindergarten class will have very different needs from a high-school commercial arts course. The latter shades off into small business/small home office territory so this article will consider low-volume "teacher-controlled" situations only.
Generally speaking, pouch laminators are easier to use, so are preferable for young children and the early grades. Roll laminators may be applicable for older students who may have larger projects to undertake. In either case, unless volume dictates otherwise, cold laminating is much preferred for reasons of safety.
Lamination width for a school application may be worth a little thought. Especially for the younger kids, big posters and suchlike may be the project while on the higher grades the output may be more restricted. Still, if the budget permits, having both an ordinary machine with a width of up to 16" or 18", plus a wide machine — 25" or 38" or 44" — may be the ideal solution.
There has apparently been something of a controversy over 25" laminators versus 27". Manufacturers have concluded that for such a slight difference in width, the extra cost of maintaining similar quality is too great to be feasible, while keeping the cost comparable would require the use of cheaper components. (See Ledco, //www.gwjco.com/school-laminator-25vs27.htm).
Most laminator manufacturers sell machines that can be used in school settings along with the supplies, but there are a few companies that specifically advertise school products.
See the page on Laminator Manufacturers for more details.