Math - Missing Piece and Place Value

As the school year goes on, the concepts and operations in math get more complex.

 We have been focusing a lot the last week on "missing part" type of story problems. This is an advanced concept and requires number sense and an understanding of how numbers fit together. It also stretches the learner to think of our equations in a different way. Instead of solving for -   3+3=___ they are trying to solve for a missing piece in ANY part of the equation - ___+2=6     or  1+____=10. Here is an example of a story problem we've been working on: Lola was making a necklace. She had 12 beads on her necklace but some of them fell off. There are 2 beads left. How many beads fell off? This concept has been challenging for the students. First we have been trying to identify the question the students are needing to answer. In this case: how many beads fell off? Then we look for information that is given to us: She started with 12 beads and there are 2 left. From there we decide if we need to add or subtract to solve for the missing piece. We will continue to work on this.

This unit develops a more abstract understanding of place value, viewing 2-digit numbers as tens and ones. This understanding of place value supports counting on and making ten strategies that students can use to become more efficient in addition and subtraction situations. In this unit students build on their understanding of adding and subtracting within 20 to develop strategies for adding and subtracting larger numbers. Students are also introduced to mentally adding to 10. These standards are grouped together because the ability to compose a ten and the ability to add and subtract ten is a crucial understanding that can help students develop number sense and proficiency with numbers and operations. Included in this unit are “Add To/Take From and Put Together/Take Apart” problems with unknowns in different positions. These problem types give students the opportunity to see subtraction as the opposite of addition in a different way than as reversing the action. Counting on strategies reinforce that subtraction is an unknown addend problem, which help students view subtraction as being just as easy as addition and emphasizes the relation between subtraction and addition.