Solidifying Single Digit Addition Skills 

Most rising first graders will have a good understanding of this topic - the last bullet will be the best practice for most students. 

• Add objects and/or shapes and have students count them at the end 

  • If this is difficult for students, do it on your own first to demonstrate (and be sure to number the objects as you go)

• Demonstrate addition of single digits using a numberline. (e.g. 4+3=7 → start at 4, move three to the right, arrive at 7).

  • We recommend this virtual number line 

• Do this with different number sets that have the same sum (e.g. 4+5=9 and 3+6=9)

• Encourage students to memorize the sums of small digits so that it can become second nature. 

  • Try using virtual flashcards (we recommend this set - it can be helpful to go through this set in order to allow kids to recognize patterns, and then shuffle them for memorization)

* Subtraction can be taught with the same concepts & tools. Word problems are especially  helpful when teaching subtraction. More advanced students may want to focus on subtraction. 

 

Comparison of Numbers

Most students will already be able to identify numbers as being “bigger” or “smaller” than other numbers. 

• Compare length and weight. Students first learn to identify the attribute being compared, moving away from non-specific language such as “bigger” to “longer than,” “heavier than,” or “more than.” 

  • This is best executed with real-life examples

  • Kids may enjoy comparing their height with items in the home

• Number comparison leads to a further study of embedded numbers 

  • e.g., “3 is less than 7” leads to, “3 and 4 make,” 7 and 3 + 4 = 7

 

Exploring the Tens Place 

Students familiarity with this topic will vary greatly because it was being taught when the shutdown was implemented. 

• Work with numbers 11-19; decompose these “teen” numbers as “10 ones and some ones” or “1 ten and some ones”

• Apply this with basic addition and comparison using 10 as a base (e.g. 12 is 2 more than 10)

  • Tip: This should establish that the number 10 is special; it is the anchor that will eventually become the “ten” unit in the place value system in Grade 1. 

  • We recommend these virtual base ten blocks and virtual number frames 

• If student feels comfortable, proceed with teen addition not based on 10 (e.g. 14+2=16)

• Overall, students must understand 

  • that the two digits of a two-digit number represent amounts of tens and ones (23 is 2 tens and 3 ones)

  • the following as special cases: a. 10 can be thought of as a bundle of ten ones – called a “ten.” c. The numbers 10, 20, 30, 40, 50, 60, 70, 80, 90 refer to one, two, three, four, five, six, seven, eight, or nine 10s (and zero 1s). 

• Check for students’ knowledge of 10-100; if they are comfortable, proceed with addition of two digit numbers and single digit numbers based on tens (e.g. 40+3=43, 70+8=78) and then not based on tens (61+5=66). 

  • Emphasize the patterns between single and double digit addition (e.g. 2+5=7 & 42+5=47)

 

The following material is generally taught in the beginning of first grade. If your student feels comfortable with the above, you may proceed with a more concrete exploration of place value.

 

Adding and Subtracting “Across Ten”

(Also referred to as “making ten,” “completing ten,” or “composing ten”)

 

For the example to the left, considering the equation 8 + 5, students must “make ten” by taking 2 from the 5 and adding it to the 8. The 8 becomes 2 greater (10) and the 5 becomes 2 lesser (3). Then students must add 10 + 3. 

 

• This concept is best taught with drawings like the one shown above, which can be shown using this virtual number frame 

• Keep in mind: Students should begin to conceptualize ten as a single unit. Also, learning to “complete a unit” (as they did in the above example) helps students in later grades to understand “renaming” in the addition process, to add 298 and 35 mentally (i.e., 298 + 2 + 33)