The World Book Encyclopedia
1977 (good time line of history and conversion tables for customary and metric)
Szabo, Dr. Michael and Trueblood, Dr. Cecil R.
A K-12 Curriculum Activities Handbook for
The Norhteastern Metric Educational Consortium, 1977 (sample activities for all grade levels in all disciplines)
Evans, Richard, Wixon, Edwin, and Hanson,Susan
Make Your Own Metric Measuring Aids
Area Cooperative Educational Services (ACES) (excellent for all levels)
These last two plus a number of “Metric Idea Exchange” pamphlets which contain topical articles on the metric system are available from the ACES office at 800 Dixwell Ave. in New Haven. There are also numerous publishers and supply catalogs offering metric materials such as Education Supplements, 163 Westport Ave., Norwalk, Conn. 06851, and Enrich, 760 Kifer Rd., Sunnyvale, CA. 94086. I haven’t reviewed these materials.
Also, SNET Co. published a nice little metric conversion booklet but I’m not sure it’s still available.