There are several editions of William Holmes McGuffey’s Eclectic Readers available online and in print. Project Gutenberg has nice .PDFs available, and selections from this could easily be projected on a screen or printed out for use by groups of students. There’s also a Google books edition of the fifth and first readers.
It’s noteworthy that many home schools and parents who wish to supplement their children’s schooling are turning back to the McGuffey readers. Their variety of readings from literature and stories with heart inspired generations previously. The final editions would challenge many in college (and perhaps might make some college bound students rethink the depth of their preparation).
The original edition were unabashedly Christian, since McGuffey was a Presbyterian pastor. His home is now a museum as part of Miami University in Oxford, Ohio, where he served during its years as a Presbyterian seminary. It’s a reminder of the days in the USA pastors were highly respected members of the community and leaders in education. Later editions toned down the Calvinism and added more readings from other areas of literature. It would seem logical to decide on one edition as a primary teaching edition, and supplement it with material from other editions as applicable.
If I were a parent in the USA nowadays, I would make sure that each child had his or her own print edition of the readers from the time that he or she began school. The price is less than many toys, and the life impact could well be much more than any toy. I think that it would also be something that many adults could do, to forsake channel surfing and TV reruns for a chapter in the McGuffey readers.