Recycle or donate them....
You could save them, but the eclipse glasses actually expire. You could recycle or donate them. To recycle them, separate the paper from the lens, throw out the lens and recycle the paper part.
Organizations like Astronomers Without Borders, Warby Parker, and Eclipse Glasses USA also have programs to reuse or recycle eclipse glasses to distribute to other areas around the world expecting eclipses in the near future.