Materials:

• Demo digit cards- one set for class use
• Small digit cards- one set for each student

Directions:

• Hand out the decimal point demo card as well as several digit cards to students. (e.g. 7, 2, 0, 4, and decimal point.)
• Students at desks also need a decimal card in addition to these same digit cards.
• Give directions for students to build a number to meet specific criteria. Students in front rearrange themselves to build a number. Students at desks arrange digit cards to build a number to satisfy the conditions.
  1. Build the largest number you can.
  2. Build the smallest number you can.
  3. Build a number less than 70.
  4. Build a number greater than 400.
  5. Build a number that is less than 400.
  6. Build a number less than 4.
  7. Build a number that is between 40 and 70.
  8. Build a different number that is between 40 and 70.
• Repeat with different digits and different directions.

Enrichment:

As students develop proficiency with this activity, select a student to give directions for building each number to encourage the use of higher-order thinking skills.

Center Activities:

• Ask students to play as partners with one partner dictating the number and the other partner arranging the digit cards. Provide sample number cards, if needed, to prompt the dictation.
• Provide copies of Build a Number Worksheet
• for students to use to create their own versions of this activity. Students should select the digits to be used and then write 5-10 Build a Number conditions. Students should create answer keys on the back of their papers. Use these student-generated activities for future place-value practice.

from:

http://www.mathwire.com/numbersense/morepv.html