BLACKBOARD BUYS AGAIN: Whispers of Blackboard’s sale may have abated since it appointed a new CEO to start the year. But the company continues to buy. Its latest acquisition: Sequoia Retail Systems, a provider of point-of-sale (POS) systems used in university bookstores, cafeterias, recreation centers and other campus-based services. (These tools, for instance, allow students to pay for meals using their school-issued ID card.) Founded in 1985, Sequoia counts “hundreds” of community colleges and multi-campus universities as users of its products.