Newspapers and similar quality materials should be photocopied onto archival quality paper to insure longevity. Black and white photos are much more stable than color prints. Use black and white if at all possible. To keep photo emulsion surfaces from sticking together, interleave the photos or sleeve them with archival quality photo envelopes. Labeling these enclosures in pencil would be useful to the intended future audience.
Burial vaults have an obvious track record and are the most commonly used containers.
Commercial time capsule products are available, but budget and space often drive the decision for local fabrication. Polypropylene, aluminum, and stainless steel are currently considered as acceptable capsule structure materials. Today's computer discs and similar electronic media will not be playable in the future. Because the aging characteristics of some plastics are not good and others are not truly known, these materials cannot be counted upon to survive in their original form.