Counting and place value 2

Students revisit how two-digit numbers are composed of tens and ones, using place value models to reinforce understanding.

Students represent the same two-digit number using base-ten blocks, expanded form, and written numerals.

Students add a multiple of 10 to a two-digit number using place value understanding, noting that only the tens digit changes.

1.NBT.C.4: Add within 100, including adding a two- digit number and a one-digit number, and adding a two-digit number and a multipl...

Students add a two-digit number and a one-digit number within 100 using strategies based on tens and ones.

1.NBT.C.4: Add within 100, including adding a two- digit number and a one-digit number, and adding a two-digit number and a multipl...

Students subtract multiples of 10 from two-digit numbers using base-ten models and place value reasoning.

1.NBT.C.6: Subtract multiples of 10 in the range 10-90 from multiples of 10 in the range 10-90 (positive or zero differences), usin...

Students use an open number line to subtract multiples of 10, connecting jumps of ten to place value understanding.

1.NBT.C.6: Subtract multiples of 10 in the range 10-90 from multiples of 10 in the range 10-90 (positive or zero differences), usin...

Students mentally find 10 more and 10 less than numbers up to 100, building speed and confidence.

1.NBT.C.5: when given a two-digit number, mentally find 10 more or 10 less than the number, without having to count; explain the re...

Students apply place value strategies for addition and subtraction to solve word problems within 100.

1.NBT.C.5: when given a two-digit number, mentally find 10 more or 10 less than the number, without having to count; explain the re...