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Introduction to Reading Signal Flags

Name of Corresponding Unit Plan: War of 1812

Grade Level: 4-12

Common Core Standards
RS9-10.4. Determine the meaning of symbols, key terms, and other domain-specific words and phrases as they are used in a specific scientific or technical context.

Content Areas: Reading, Social Studies

Recommended Length/Duration: 45-60 minutes

Learning Goals: Students will become familiar with the International Code of Signals flags. Students will decode messages by identifying the signal flag patterns.


  1. Describe or have students read the history of signal flags.
  2. Distribute copies of the International Code of Signals flags. Review the characteristics of the various flags. Ask students if there are any flags they think could be easily confused (e.g. M-V, R-X, 4-8, T-3).
  3. Distribute sample worksheet for decoding. Instruct students to identify each flag in the message and write the corresponding letter in the black space below.
  4. Review responses once students have had a chance to decode the sample.
  5. Have students encode their own message using the blank grid.
  6. Have students exchange papers and decode the message their partner encoded.
  7. When students have decoded the messages, have students share the messages they decoded.

Assessments: Assess worksheets for accuracy.

Materials/Resources: International Code of Signals flag chart and worksheet, Crayons, markers, colored pencils

Special Considerations: Students with visual impairments could be assigned a partner to work with.

Extensions: For homework students could be asked to continue to encode messages for decoding by a partner the next day. Students could make a set of signal flags by having each student make one flag from a sheet of paper or fabric. Students may want to learn more about the International Code of Signals, Pub. 102 available to download at:
Students might be interested in learning Morse Code or semaphore systems.