Apple's Macs rack up more than 1/4 of back-to-school PC sales in 2014

Mac sales were up 14 percent year-over-year, compared to a 3 percent decline for Windows-based computers. Apple's MacBook line was particularly strong, according to market research firm NPD, up 16 percent over the year-ago period.

Google's Chrome OS also pushed ahead, adding 1.2 percentage points to finish with 4.5 percent of the market, a 32 percent year-over-year increase for the nascent web-centric platform.

Much of the non-Apple volume consisted of ultra-low-cost machines, the data suggests. Many Chromebooks —  laptops running Chrome OS - come in at less than $300, and sales of sub-$300 Windows-based computers were up 37 percent with an average selling price of $242.

"After a slow start, aggressive pricing and robust selection drove significant volumes towards the end of the Back-to-School season, making it a very strong year," NPD executive Stephen Baker said in a release. "Due to the success of the aggressive Windows notebook pricing during Back-to-School we could see a much more aggressive pricing strategy this holiday season as the seemingly stable PC volume environment emboldens the PC OEMs and the OS and chip suppliers to make a grab for market share while the industry remains relatively steady."

Apple does not compete in the ultra-low-cost segment, making its ability to gobble up share even more impressive. The $899 11-inch MacBook Air is the company's least-costly offering, and the Mac's average selling price comes in well over $1,000.

Still, there are options for consumers looking for more affordable Macs. For instance, AppleInsider's own Mac Price Guide offers readers a number of coupons and discount incentives from Apple Authorized Resellers that knock down the price of more costly Macs by several hundred dollars, while also offering entry-level options in the sub $800 range.