During our math time this week we continued to break apart larger numbers into smaller partners. We used whiteboards and markers, counters, stair steppers, and activities from our math workbook to visualize the partners, switch partners, and doubles partners for the numbers 6, 7, and 8. Challenging your first grader to write and show each set of partners in a variety of ways has helped to increase number sense and flexibility with these numbers.
We also continued to use our knowledge of partners and patterns to practice addition (+0, +1, +2) and subtraction (-0, -1, -2) facts. This week in particular, we practiced adding and subtracting doubles partners (1+1, 2-1, 2+2, 4-2, 3+3, 6-3, etc.), and discovered that a number minus itself equals 0 (8-8 = 0).
We are off to a great start with our wonderful math program. During the first two weeks of school, we’ve been visualizing, representing, and breaking apart numbers using a variety of math tools: counters, stair steppers, and number cards. When we break apart a number, we take a larger number and split it into two smaller numbers. We call the two smaller numbers partners because when we add them together they equal the larger number. So far, we’ve discovered the partners (and switch partners) for 2, 3, 4, and 5. (Check out the chart below!) We have also used our knowledge about partners and patterns to solve addition (+0, +1, +2) and subtraction problems (-0, -1, -2).
This week, we took our Unit 7 assessment – our first graders did great!!!
We started working on adding two 2-digit numbers together. We introduced a strategy called New Ten Above.
Our goal is to understand that sometimes when we add two-digit numbers – we make a new ten!!!
We continued to study shapes during our math time this week. We started the week combining triangles, rectangles and squares to form new shapes. We learned about: rhombuses, trapezoids, parallelograms, and hexagons. We also found that we could combine and transpose our shapes to create patterns.
Later in the week we began exploring with 3-dimensional shapes! We touched on the following shapes…
We learned about the attributes of each of these shapes. We also briefly discussed how these 3-D shapes compare to the 2-D shapes. For example: the 3-D sphere is just like a 2-D circle and the 3-D rectangular prism is just like a 2-D rectangle. We combined different shapes together to create new shapes and also tried to break large shapes apart into smaller ones.
Then, we moved into measurement. We discussed how in the old days before rulers were invented, people used to use their body parts to measure objects. This kids couldn’t believe this was true and brought up a very big problem… our feet and fingers are different sizes! We realized that when we use a common unit – like a paperclip – we all get the same results. To test this theory, we used paperclips to measure various things in our math book and around the room.
We also introduced the word “length” and talked about how to line up measurement tools properly to get the most accurate measurement. We compared lengths of objects from shortest to longest and longest to shortest (1, 2, 3).
During our math time this week we studied some familiar shapes: rectangles, squares, triangles and circles. We learned that every shape has special attributes that are always true!!
We also learned that shapes can be divided into equal parts. When a shape is broken into two equal parts we call these halves. When a shape is broken into four equal parts we call these fourths. It’s important to understand halves and fourths especially when we are trying to share something (like a pizza, cookie, or granola bar) equally.
This week, our mathematicians reviewed the two different kinds of clocks that we use in everyday life that are called an “analog” clock or a “digital” clock. We discussed that the shorter hand always points to the hours and the longer hand always points the minutes.
We spent lots of time reviewing and practicing drawing the time on an analog clock and on a digital clock! The hardest part for the kids is to remember that when it is a half hour, the hour hand is half way past that hour (they often read it as the next hour ahead instead of the hour it is half past).
This week our mathematicians reviewed for and took our Unit 6 test. This is one of our most challenging units of the year and our first graders performed very well. Look for your child’s math test to come home next week!
On Friday, we begin studying clocks. Our first graders learned that the two different kinds of clocks that we use in everyday life are called an “analog” clock or a “digital” clock. We discussed that the shorter hand always points to the hours and the longer hand always points the minutes. We can’t wait to learn more about telling time next week!
During our math time this week we continued to study LARGE, TWO-DIGIT numbers. In particular, we used the greater than, less than, and equal to symbols ( >, <, = ) to compare these numbers. When we compare numbers, we stressed the importance of building each number with ten sticks and ones to easily identify which number has more tens. If both numbers have the same amount of tens, then we can compare the ones to find the greater number. Our first graders quickly noticed that the greater than and less than signs look like a “hungry mouth” ready to gobble up which ever number is greatest.
Just be careful… don’t let number like: 29 & 92 or 45 & 54 or 78 & 87 – trick you!!! Build those numbers and pay attention to the tens!!! Please review this concept with your first grader, if you notice him or her getting a little confused on the homework.
This week we also practiced adding ones numbers (1, 2, 3, 4, 5, 6, 7, 8, 9) together, and tens numbers (10, 20, 30, 40, 50, 60, 70, 80, 90) together. Our first graders worked hard to notice which numbers they were working with so they could accurately represent each equation. In order to prove our work, we used ten sticks and circles to help us find the missing total.
After reviewing the MAKE A TEN STRATEGY, we took a math quiz, which the students all did very well on. Then, we moved on to studying our doubles facts. Many of our first graders know the first 5 doubles in a snap. The final 5 doubles were a little tougher.
We talked about how we can use what we know about doubles to help us solve other equations. We noticed that there is often a set of doubles that can be found hiding inside an equation. If we can find the hidden double, all we need to do is add one or subtract one to solve the equation. For example:
We will continue to work on our doubles facts, so our first graders can more easily use the Doubles +1 and Doubles -1 strategy. It would be wonderful if your child could practice their doubles facts at home too!! Practice makes permanent!!
We also studied some LARGE, TWO-DIGIT numbers this week — some of the biggest numbers that we’ve worked with so far this year! We noticed that every 2-digit number has a place to show the tens hiding inside along with a place to show the extra ones. We also represented these numbers using ten sticks and circles, and wrote an equation to match our work.
Since we were working with two digit numbers, we spent a lot of time counting tens and ones this week too. We were able to do this practice using ten sticks and circles, the number path on our whiteboards, and boxes/jars of objects. Our first graders learned to count the tens first and then “freeze” before counting up the extra ones. Taking the time to “freeze” is an important strategy that helps our students recognize when it’s time to switch from counting by 10s to 1s.
We can tell that our first graders are really beginning to understand the place value of these larger numbers!!!