Since the debut of the iPad, tablets have captured the imagination of consumers. In just one year, the iPad surpassed even the most optimistic of projections to define a brand new product category and become the best-selling gadget of all time, and Forrester analysts project that in 2011, tablet sales will more than double. But are tablets ready for the classroom? Asks Vineet Madan, vice president of McGraw-Hill Higher Education eLabs for Mashable…