NIST LC 1140 - Metric Pyramid is a helpful study aid that can be easily constructed with yellow cardstock to keep common approximate unit conversion factors for mass, length, area, volume, temperature, and energy close at hand. It's a great homework helper!
SP 304A - SI Measurement System Chart explains the 7 base units of the SI, prefix symbols, and features the Measurement League: Guardians of the SI. Submit hard copy requests to TheSI@nist.gov or print a copy (select “print to fit”). Original dimensions: 279 mm by 432 mm (11 in by 17 in).
Our website has numerous educational materials that can be downloaded and freely reproduced. These resources are helpful to students as they become familiar with the SI, develop reference points or that innate understanding of how much a quantity is, and learn more about SI basics. Your students may find Everyday Estimation and Becoming Familiar with the SI helpful. In addition, there are several Unit Conversion resources available.
One recommended education best practice is to teach the SI by using the SI. Students must build proficiency and confidence working with metric measurements before they can effectively make comparisons with other measurement systems. Use single system measurement tools whenever possible. Using dual unit measuring equipment can confuse learners because it is easy to select and use the wrong scale. When possible, acquire metric measuring devices (meter sticks, kilogram or gram scales, and Celsius thermometers). If dual unit measurement tools are used (e.g., those using U.S. customary units), block the non-metric units from view. For example, use opaque tape, an index card, or paint to cover up inches on a dual unit ruler.
Metric rulers are available from many retail vendors, which can be identified by using search terms such as "metric rule," "meter stick," or "metric stick." Printable rulers such as the centimeter Color-square rules, can be color printed on to overhead transparency sheets to make inexpensive metric rulers. You may also be interested in similar printable teaching aids that create a liter cube or a cubic decimeter box, which are easily constructed using cardstock.