https://www.khanacademy.org/math/cc-2nd-grade-math/cc-2nd-add-subtract-100/cc-2nd-math-strategies-for-adding-within-100/v/adding-by-getting-to-group-of-10-first 2021-06-24T19:33:07Z Adding by making a group of 10 Sal adds 5+68 by breaking the 5 into a 2 and a 3. video https://cdn.kastatic.org/googleusercontent/-uz_7SXu4tIiihh7ZwecHu3CVQd903F_l6W-g433-xf2m1xim7O5Q2yuyV6A9s9DJPcEq5yXBoJkQcfpWcG6zG80 Adding by making a group of 10 Sal adds 5+68 by breaking the 5 into a 2 and a 3. https://cdn.kastatic.org/ka-youtube-converted/DzJvR56Suss.mp4/DzJvR56Suss.mp4 170 Addition within 1000 (with and without regrouping) https://www.khanacademy.org/math/cc-2nd-grade-math/cc-2nd-add-subtract-100/cc-2nd-math-strategies-for-adding-within-100/v/example-exercises-on-ways-to-add-two-digit-numbers 2021-06-24T19:33:06Z Strategies for adding 2-digit numbers Sal goes through multiple strategies for adding 2-digit numbers. video https://cdn.kastatic.org/googleusercontent/Dc1DBnCBDQ3eqejQ5j5hQP8dZJ0l9eJMafRdQ4SUNJNSTC-fOTKuRUzeGMY8IWeYQKldWWqESdV1atzJKqWtJGbemQ Strategies for adding 2-digit numbers Sal goes through multiple strategies for adding 2-digit numbers. https://cdn.kastatic.org/ka-youtube-converted/kMHFY6ZrKbU.mp4/kMHFY6ZrKbU.mp4 196 Addition within 1000 (with and without regrouping) https://www.khanacademy.org/math/cc-2nd-grade-math/cc-2nd-add-subtract-100/cc-2nd-math-strategies-for-adding-within-100/e/making-100 2026-04-08T01:15:04.085520103Z Add 2-digit numbers by making tens Practice adding two-digit numbers by making groups of ten.  Lindsay Spears exercise https://www.khanacademy.org/math/cc-2nd-grade-math/cc-2nd-add-subtract-1000/cc-2nd-add-ones-tens-hundreds/v/adding-hundreds-tens-and-ones 2021-07-06T11:21:36Z Adding 1s, 10s, and 100s Sal adds 3-digit numbers by adding ones, tens, and hundreds. video https://cdn.kastatic.org/googleusercontent/z7b-NtC_5jkxqVXl0tiaHRuWttWMBKNMUl1DpurWULmT96DRQFGDWkDJCbytpgUM-QTzK0T4-RreH7zw0QadbCt_ Adding 1s, 10s, and 100s Sal adds 3-digit numbers by adding ones, tens, and hundreds. https://cdn.kastatic.org/ka-youtube-converted/SCBp0d6zR2I.mp4/SCBp0d6zR2I.mp4 217 Addition within 1000 (with and without regrouping) https://www.khanacademy.org/math/cc-third-grade-math/imp-addition-and-subtraction/imp-strategies-for-adding-two-and-three-digit-numbers/v/breaking-apart-three-digit-addition-problems 2021-04-03T21:31:52Z Breaking apart 3-digit addition problems Sal shows ways to break up addition problems using place value. video https://cdn.kastatic.org/googleusercontent/wunViDe_30HF0vaOQKWzFlnbDnovByLHD6W_MHoXTcJU4iKfPHyysWVKxD_LOP6GpxkXjkabcgp0HYMbOOAiGuM Breaking apart 3-digit addition problems Sal shows ways to break up addition problems using place value. https://cdn.kastatic.org/ka-youtube-converted/Hc9mcx739js.mp4/Hc9mcx739js.mp4 222 Addition within 1000 (with and without regrouping) https://www.khanacademy.org/math/cc-third-grade-math/imp-addition-and-subtraction/imp-strategies-for-adding-two-and-three-digit-numbers/e/break-apart-three-dig-add 2022-07-27T14:52:42.217615992Z Break apart 3-digit addition problems Practice breaking apart big addition problems using place value. For example, 234+567 is the same as 200+500+30+60+4+7. Lindsay exercise https://www.khanacademy.org/math/cc-2nd-grade-math/cc-2nd-add-subtract-1000/cc-2nd-add-ones-tens-hundreds/v/adding-ten-or-one-hundred 2021-05-18T23:20:46Z Adding 10 or 100 Sal adds 1, 10, or 100 to a number. video https://cdn.kastatic.org/googleusercontent/OW9E4ZsncTq_E03bNQ32Jz599ZQ1jPMw4pidJlfFt2ZyqNkzX9WlEvJH5CF5PwU1hanuI01-fuL429-60o7ZReXX9A Adding 10 or 100 Sal adds 1, 10, or 100 to a number. https://cdn.kastatic.org/ka-youtube-converted/wwO6DjL_wFw.mp4/wwO6DjL_wFw.mp4 239 Addition within 1000 (with and without regrouping) https://www.khanacademy.org/math/cc-2nd-grade-math/cc-2nd-add-subtract-1000/cc-2nd-strategies-for-adding-two-and-three-digit-numbers/e/add-within-1000--level-1 2026-04-08T01:15:04.085520103Z Add 10s and 100s (no regrouping) Practice solving problems like 344+20 and 344+200. Sharon Friedman exercise https://www.khanacademy.org/math/cc-2nd-grade-math/cc-2nd-add-subtract-1000/cc-2nd-strategies-for-adding-two-and-three-digit-numbers/v/adding-three-digit-numbers-without-regrouping 2021-07-06T11:21:37Z Adding 3-digit numbers (no regrouping) Sal adds 327 + 251 thinking about place value. video https://cdn.kastatic.org/googleusercontent/TAIc_HqezyamXGSasYwarzgI7AxBSXA1RJEd-EPwEeIqbxPxq9fD-KtuGAbeMqAQ6YR0JxV3LRxUbFaD7Au6f7A4Qw Adding 3-digit numbers (no regrouping) Sal adds 327 + 251 thinking about place value. https://cdn.kastatic.org/ka-youtube-converted/d3109sV6izY.mp4/d3109sV6izY.mp4 160 Addition within 1000 (with and without regrouping) https://www.khanacademy.org/math/cc-third-grade-math/imp-addition-and-subtraction/imp-adding-with-regrouping-within-1000/v/why-carrying-works 2021-06-24T19:33:08Z Using place value to add 3-digit numbers: part 2 Learn to use regrouping to add 536+398. Sal Khan video https://cdn.kastatic.org/googleusercontent/X8FnO5b81_wMHWP2PvZ2mJncM975NVDzuSfrAe6X8XktnEbHSZ6kR6o_QRR0DBFnr3gbI_Vn8KSskomMpgUdd0x6 Using place value to add 3-digit numbers: part 2 Learn to use regrouping to add 536+398. https://cdn.kastatic.org/ka-youtube-converted/O9zSHs1TWMM.mp4/O9zSHs1TWMM.mp4 150 Addition within 1000 (with and without regrouping) https://www.khanacademy.org/math/cc-third-grade-math/imp-addition-and-subtraction/imp-adding-with-regrouping-within-1000/v/example-adding-with-carrying 2021-07-07T20:19:26Z Adding 3-digit numbers Learn to use regrouping, or carrying to add 709+996, 373+88, and 149+293. Sal Khan video https://cdn.kastatic.org/googleusercontent/hgHcTsRKnLiu92VE5fvxzDn7XZKd7qcCjoYBO84ozDq0K8hGjQPFJoZ9_CfOBHip-hg5Hhw_4u7AB5kY5x7f7RoJ Adding 3-digit numbers Learn to use regrouping, or carrying to add 709+996, 373+88, and 149+293. https://cdn.kastatic.org/ka-youtube-converted/9hM32lsQ4aI.mp4/9hM32lsQ4aI.mp4 184 Addition within 1000 (with and without regrouping) https://www.khanacademy.org/math/cc-2nd-grade-math/cc-2nd-add-subtract-1000/cc-2nd-add-ones-tens-hundreds/e/add-within-1000--level-2 2026-04-08T00:16:02.937952483Z Add within 1,000 using place value blocks Practice adding numbers using place value blocks. All numbers used and sums are within 1000. Sharon Friedman exercise https://www.khanacademy.org/math/cc-third-grade-math/imp-addition-and-subtraction/imp-adding-with-regrouping-within-1000/e/addition_4 2026-04-30T18:30:41.846286703Z Add within 1000 Practice adding three-digit numbers. All sums are 1000 or less. Lukas Domagala exercise https://www.khanacademy.org/math/cc-sixth-grade-math/cc-6th-expressions-and-variables/properties-of-numbers/a/properties-of-addition 2023-12-11T22:10:22.66384181Z Properties of addition Explore the commutative, associative, and identity properties of addition. article