Learning addition and subtraction facts? Use Crayola® Model Magic® to make your own base 10 sticks. What a great learning tool!

• 1.

  Find out about the world’s different number systems. You’ll discover the Arabic, Chinese, Egyptian, Gothic, Greek, Roman, and Sanskrit number systems. The decimal system, which is what is used in the United States and most other countries today, probably arose from counting on 10 fingers. Our ancestors counted on their fingers until they reached 10, made a mark in the sand, then continued to count on their fingers.

• 2.

  Bones found in Africa, dating to 37,000 years ago, have 29 evenly spaced notches on them. These were tally sticks. Anthropologists think these represent the number of days in a moon cycle. In a hunter/gatherer society, it is possible that tallies were kept to record how many days were spent in one location. After a certain number of days, the hunters/farmers would move on, perhaps to conserve resources.

• 3.

  Cut the straws. To make your own tally system with base 10 sticks, cut a plastic drinking straw into 10 equal lengths. Use the 1/10 length to measure and cut additional straws into 2/10, 3/10, 4/10, 5/10, 6/10, 7/10, 8/10, and 9/10 lengths. An uncut straw will equal 10/10. Cut enough straws so that you have several of each length.

• 4.

  Mix your colors. Use Crayola Model Magic to color code each length. You will need 10 colors of Model Magic. To create 10 colors, blend two or more colors of the modeling compound together. For example: Mix blue and yellow Model Magic to make green. Mix yellow and red to make orange. Mix red and blue to make purple. Add white Model Magic to orange to make a light orange. Add white Model Magic to blue to make a lighter blue. Make a lighter green and a lighter red using the same method.

• 5.

  Make a chart with Crayola Fine Tip Markers indicating what color each length will be.

• 6.

  Prepare your sticks. Roll out each Model Magic color into a thin layer. Carefully wrap each straw length with its designated color. Cover the ends of the straws. Gently press each stick on a flat surface to create four flat sides and two flat ends.

• 7.

  Carefully use a craft stick to indent notches representing 1/10 on each of the four sides. For example, the "two" stick will have one notch in the middle. The "three" stick will have two evenly spaced notches. Air-dry all of your base 10 sticks overnight.

• 8.

  Add and subtract! Use your base 10 sticks to help you solve addition and subtraction problems. When adding, place the sticks end to end, from left to right, to make a train. Find a single rod to match the length of the train. The addends are the cars of the train. The sum is the single rod that matches the train length. When subtracting, place the smaller rod on top of the larger one. See what length rod is needed to make a matching train. The difference is the rod that fills that gap.

• 9.

  Challenge your classmates to solve base 10 problems you create yourselves.

Standards

• LA: Ask and answer such questions as who, what, where, when, why, and how to demonstrate understanding of key details in a text.
• LA: Use information gained from the illustrations and words in a print or digital text to demonstrate understanding of its characters, setting or plot.
• LA: Know and apply grade-level phonics and word analysis skills in decoding word s.
• LA: Read with sufficient accuracy and fluency to support comprehension.
• LA: Participate in shared research and writing projects.
• LA: Engage effectively in a range of collaborative discussions with diverse partners on grade level topics, texts, and issues, building on others' ideas and expressing their own clearly.
• MATH: Use addition and subtraction within 100 to solve one- and two-step word problems involving situations of adding to, taking from, putting together, taking apart, and comparing.
• VA: Use visual structures of art to communicate ideas.
• VA: Select and use subject matter, symbols, and ideas to communicate meaning.

Adaptations

• Possible classroom resources include: Sparrows Singing: Discovering Addition and Subtraction by Megan Atwood; The Good Neighbors Store an Award; A Cheesy Mouse Tale of Addition with Regrouping by Mark Atwood; The Good Neighbors' Cheese Feast; A Cheesy Mouse Tale of Subtraction with Regrouping by Mark Ramsay; A Fair Bear Share by Stuart J. Murphy
• In small groups, students read or listen to The Warlord's Beads by Virginia Pilegard, which is about the abacus. After the read, encourage students to investigate how the first abacus is created and how to make one of their own. How does the abacus help with addition and subtraction?
• In small groups, students compose original word problems involving addition and/or subtraction. Students write their original problems on index cards, including the solution on the back side of the card. Groups swap cards with other classmates and use their base ten blocks to assist with finding solutions.