Base Ten: Building Understanding of Place Value
I am always amazed by the number of students that don’t understand that our place value system is based on the number 10. It’s one of the first questions I ask when I walk into a classroom and most of the time students have no idea! Everything in our number system revolves around the number 10 and for students to understand adding, subtracting, fractions, decimals, etc., they need to understand how the number 10 is the foundation of number sense. There are many little games and activities we can do to help our children understand this concept and become more fluent in counting and using mental math.
1. Skip count by 10s: many children memorize at an early age how to count by 10s; 10, 20 30, and so on. It is from rote memory that they develop this skill but it does not mean they really understand how to count by 10s. Encourage your children to start at a different number and count by 10s. For example 4: 4, 14, 24, 34, 44, 54, 64, 74, 84, 94, 104….and so on. Have them do this backwards. Start at a number (94) and have them count back by 10s.
2. Skip count by 100: Follow the activity from above but this time count by 100, but start at a different number. For example 9: 9, 109, 209, 309, 409, 509, 609, 709, 809, 909, 1,009… It is very telling to see where children struggle the most in their counting. It gives great insight into their understanding. As a challenge, have them count back by 100.
3. Multiply by groups of 10: Students need to understand that our place value system increases and decreases by groups of 10. So we want to build their mental math capability by multiplying and dividing by 10. Provide a starting number and have your children multiply the number by 10, 100, 1,000. For example 45: 450; 4,500; 45,000. Encourage them to see patterns in these numbers.
4. Divide by groups of 10: Follow the activity from above but now divide by groups of 10. For example: 80,000: 8,000, 800, 80, 8. This activity sets up the understanding of decimals, which begins in 4th grade. As a challenge, begin to incorporate these activities with decimals. For example 9.02: 9.02 x 10 = 90.2; 902; 9,020….
If students have a strong sense of place value and the base 10 system, they will be able to apply it to all types of areas as they get older and move into middle school – decimals, percents, fractions, scientific notations, etc. These activities will help your children become flexible with numbers and develop a deeper understanding of the Base 10 System.