At Boston-based Houghton Mifflin Harcourt, for instance, programmers scrambled to create an iPad-specific secondary school program starting almost as soon as Apple unveiled the tablet in spring 2010.

The publisher’s HMH Fuse algebra program, which became available at the start of the 2010 school year, was among the first and is a top seller to districts. Another algebra program and a geometry offering are coming out now.

The HMH Fuse online app is free and gives users an idea of how it works, and the content can be downloaded for $60. By comparison, the publisher’s 950-page algebra text on which it was based is almost $73 per copy, and doesn’t include the graphing calculators, interactive videos, and other features.

For a school that would buy 300 of the textbooks for its freshman class, for instance, the savings from using the online version would be almost $4,000.

Jay Diskey, executive director of the Association of American Publishers’ schools division, said all of the major textbook publishers are moving toward electronic offerings, but at least in the short term, traditional bound textbooks are here to stay.

“I think one of the real key questions that will be answered over the next several years is what sort of things work best in print for students and what sort of things work best digitally,” Diskey said. “I think we’re on the cusp of a whole new area of research and comprehension about what digital learning means.”

For more news about iPads in education, see:

New Jersey district plans iPad-only algebra course

Five ways readers are using iPads in the classroom

Schools see rising scores with iPads

iPads take a place next to crayons in kindergarten

10 of the best apps for education