Use place value understanding and properties of operations to add and subtract
Add within 100, including adding a two-digit number and a one-digit number, and adding a two-digit number and a multiple of 10, using concrete models or drawings and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method and explain the reasoning used. Understand that in adding two-digit numbers, one adds tens and tens, ones and ones; and sometimes it is necessary to compose a ten.
Related Lessons
Lesson 317
Join Mrs. Markavich with a Mystery Math Mistake - see if you can help D.C. with an addition mistake! We'll solve word problems with unknowns in different positions.
Lesson 318
Join Mrs. Markavich with a Mystery Math Mistake - see if you can help D.C. and Value Pak with an addition mistake! We'll also solve word problems and write equations to match.
Lesson 314
Join Mrs. Markavich with a Mystery Math Mistake - see if you can help D.C. with his strategy! Next, can you help us measure with different units (small and large paper clips, connecting cubes and small cubes)?
Lesson 307
Join Mrs. Markavich for a subtraction word problem with Professor Barble. Next, get ready to make sense of equations that have a missing part and look out for D.C. as we make a ten to solve addition easier!
Lesson 308
Join Mrs. Markavich for a missing addend word problem with Professor Barble. Next, we are going to look closely at addition problems to see when we make a new ten or when we don't. You will be an expert and looking carefully at addition problems!
Lesson 309
Join Mrs. Markavich for a missing addend word problem with Professor Barble! Look out for two of our Math Might friends D.C. and Value Pak as they help us learn to add two-digit number in more than one way!
Lesson 310
Join Mrs. Markavich for a missing addend word problem with Professor Barble! Next we are going to spend some quality time with Value Pak as we learn to add by adding tens-and-tens then ones-and-ones!
Lesson 311
Join Mrs. Markavich for a Mystery Math Mistake with Value Pak - they need your help! Next, start to compare and order objects by length.
Lesson 312
Join Mrs. Markavich for a Mystery Math Mistake with Value Pak, they need your help! Next, explore measuring by choosing objects to indirectly compare.
Lesson 305
Join Mrs. Markavich for a word problem with her friend Professor Barble! Next, get ready to have some fun with Value Pak as we add 2-digit numbers using base ten strategies!
Lesson 306
Join Mrs Markavich with a part-whole missing addend word problem with her friend Professor Barble. Next, get ready to have some fun with D.C. adding 2 digit-numbers to a 1 digit number by making a friendly decade number!
Lesson 303
Join Mrs. Markavich for a word problem with her friend Professor Barble! Get ready to have some fun adding tens and ones with ten frames and with a game called "What did I Add"!
Lesson 304
Join Mrs. Markavich for a word problem with her friend Professor Barble! Next, we will work on adding two-digit numbers and matching equations!
Lesson 301
Join Mrs. Markavich & Dotson for a Numeracy Talk with the Counting Buddy Senior, then we show you different ways to decompose and compose 2-digit numbers!
Lesson 302
Join Mrs. Markavich & Dotson to talk about numbers with the Counting Buddy Senior! Get ready for Value Pak to show you how different ways to compare 2-digit numbers!
Lesson 215
Join Mrs. Markavich for Numeracy Talk with Dotson working on conservation to 20. Get your math brain ready to have some fun with adding two-digit numbers.
