Cubify from 3DSystems http://cubify.com/
Cube 3D Printer Features
• Prints objects up to 140 x 140 x 140 mm
• EZ Load Print Cartridge
• Durable, ABS Plastic in 10 Optional Colours
• USB & WI-FI Connectivity
• Single Jet Layer Thickness –  250 microns, 0.25 mm
• Supports: Fully Automated; Easy to peel off
• One Cartridge prints 13 to 14 mid-sized creations.
Software supplied reads STL files.
Approx. price £950. 

Ultimaker www.ultimaker.com
Kit to build approx. price £980.

• An extremely large build volume, 21x21x20.5 cm (L/W/H), while having a very desktop friendly footprint of only 35x35 cm.
• The fastest controlled horizontal acceleration in the market, allows for extremely fast printing.
• Connect the machine to your computer's USB port, Drivers for Windows, Mac and Linux are available.
• Capable of printing with biodegradable PLA plastics and ABS. This allows for extremely affordable printing (plastics offered here). Feel free to use other materials!
• Theoretical resolution: 0.0125 mm for the X and Y axis, the Z-axis is even more accurate!

Company based in the Netherlands.

• Dimensions 360 x 360 x 320 mm (excluding material holder)
• Weight 2.7 kg
• Printable area: 210 x 160 x 100 mm
• Printing Speed: 40+ mm/sec
• Layer thickness: 0.125 – 0.3 mm
• Nozzle size: 0.5 mm (good for fast printing)
• Filament size: 3 mm
• Material: PLA (Poly Lactic Acid: biodegradable material)
• Supplied complete with software
• Maxit — at a glance
• Super light and easy to transport
• Very simple to assemble (under a day)
• Reliable support
• Compatible with CAD software — both open source and commercial
• Price: £995

 RapMan 3.2 3D printer kit for education includes:

• A pre-built hot end (the really fiddly and annoying part)
• A 25-way D-sub connector with a screw terminal (eliminates the need for a soldering iron)
• USB drive including teaching and learning resources for 3D printers in the classroom
• RapMan toolkit
• Single head material starter pack (6kg) Includes: ABS: White, Green and Black (1kg [2.2lb] each roll); PLA: Solid White, Solid Yellow and Translucent Red: (1 kg [2.2lb] each roll)
• USB drive including teaching and lesson ideas
• Price: £1,238.00

http://www.bitsfrombytes.com/store/rapman-32-3d-printer-kit-education

Makerbot http://www.makerbot.com/ 
Approx. price £1,500 from http://robosavvy.com/site/ or
http://www.reprapcentral.com/ 
 
With a resolution capability of 100 microns and a massive 410 cubic inch build volume, the MakerBot Replicator™ 2 Desktop 3D Printer requires no assembly and is the easiest, fastest, and most affordable tool for making professional quality model suitable for use in schools. The software can be installed on multiple computers to prepare the models. Models can be saved to SD card which can then be used for printing, making it very easy to share the printer in a classroom or a professional lab.

Features (pdf download):
• High Resolution: down to 100 micron for smooth objects • Multiple Resolution/Speed settings for fast prototyping or high quality prints: Fine / Normal / Fast print quality selectable by the user. • Material: 1.75mm filament made of PLA (Poly Lactic Acid), a biodegradable plastic • Build Volume:  28.5cm x 15.3cm x 15.5 cm • Physical dimensions (without spool): 49cm x 32cm x 38 cm • Frame: powder coated steel chassis for robustness and to handle high speed printing • XYZ Bearings: wear-resistant, oil-infused bronze for lower maintenance • No assembly required • Includes a 1 lb spool of Natural PLA filament. • Software: Makerware bundle included (can be installed on multiple computers) 
• Set-up and maintenance procedures illustrated in simple step-by-step video tutorials

Makerbot is based in New York.
Robosavvy is based in the UK and provides the printers, local support and training to professionals and schools (Aurea Sequeira, This e-mail address is being protected from spambots. You need JavaScript enabled to view it , Phone: 0203 129 2209)

 
More Expensive machines:

Dimension Elite 3D Printer
Build Real Plastic Parts from 3D CAD Models Features SST technology and fine resolution printing so ideal for demanding applications where colour models, excellent surface finish and fine detail is needed. Approx, price £21,000

3D Matrix Printer
Uses A4 paper to build 3D objects.
See http://www.mcortechnologies.com/index.html

Solido SD300 Pro Offers schools a fantastic price package with very low operational costs and low price material kits.
Contact Ben Peterson:  This e-mail address is being protected from spambots. You need JavaScript enabled to view it
Phone: 07771 813790