Those who were enthralled by Apple’s unveiling of its latest iPhone might have missed an even more enticing introduction for schools: the company’s latest iMac all-in-one systems now have more power, thanks to the use of Intel’s Haswell processors. There are two versions that come with 8GB of RAM and a 1TB hard drive, but differ as to the processor, screen and graphics. For instance, the 21.5-inch iMac now has a 2.7GHz quad-core Core i5 chip that can run as fast as 3.2GHz; it starts at $1,300. Too small? There’s also the 27-inch screen machine that uses the 3.2GHz Core i5 processor that can be boosted to 3.6GHz and has Nvidia’s GeForce GT 755M graphics with either 1- or 2-GB video memory. The larger iMac starts at $1,800.