We've been delving deeply into a few math concepts lately: addition, subtraction, shapes, and those tricky teen numbers. Below are some games and activities we've done to deepen our understanding!
Understanding subtraction as taking away
We played a game called Clear the Deck, in which the first person rolls two dice: one with an addition or subtraction sign, and one with numbers 1-6. If they roll a subtraction sign, they need to take away that number of circles from their deck. If they roll an addition sign, they need to add that many back on. The first person to clear their deck wins!
Addition and Subtraction Stories
We tell addition and subtraction stories (also known as story problems) several times a week, and practice writing out the number sentences and drawing a picture to go with. In kindergarten, we encourage kids to use their fingers and drawings to demonstrate their answer, because this helps it stay concrete in their minds.
Geoboards
These boards are equipped with small nails that allow for rubberbands to be stretched out in different shapes. We had lots of explore time with the boards, and then practicing making certain shapes - which helps students attend to the number of sides and corners that each shape has.
Understanding Teen Numbers
We made "teen scenes" to show that teen numbers are 10 plus some ones. Students could use any object in their scenes. The choices shown below were flowers, people, and ipads!
Every day we have math for 45 minutes (in addition to 15 minutes of calendar math in the morning). I am very lucky to have one assistant teacher and two high school tutors during this time, so we can easily break the kindergarteners up into four groups and have four teacher-led centers! Of course, the activities are very hands-on and the student mostly direct themselves. But the grown-ups are there to teach them the new game and emphasize important concepts, or help kids who are struggling with the task. I try to have four different types of centers each day, based on the Common Core standards and our math curriculum, Everyday Math.
1. Math Games
Math games allow the kids to develop number sense, practice counting and one-to-one correspondence, and try new skills such as measuring and graphing.
In this game, kids roll a pumpkin dice and graph their results!
In this game, kids spin a spinner, count the number of apples, and make that amount using cubes on the side.
2. Math Fact Practice
Fact fluency is very important for kindergarteners. By the end of kindergarten, they need to be comfortable adding and subtracting within 5 automatically, as well as able to use objects, drawings, equations, and their fingers to add and subtract within 10. So the more practice we can get, the better! Below is an example of a fact practice game.
Kids roll two dice and add the numbers together, then find the answer on their Halloween sheet and color it in!
3. Math Manipulatives
Manipulatives are objects that kids can sort, stack and build with, to help them increase their skills at patterning, sorting and engineering. This center often seems like just free play, but is really disguised hands-on learning as well!
Sorting coins
Unifix cubes
The ever-popular "wheels" as we call them (I don't actually know their official name!)
4. Math Journals
This center is with me, and is one of my favorite times to assess kids' thinking on challenging concepts. We usually do some sort of problem-solving question of the day. For example, below I gave them a piece of paper that said "Can you fill a circle using only squares?" (from this generous teacher who shared her idea on her blog). I gave each student a bunch of squares, and they all tried various ways to fill it up. In the end, we figured out that, no, you can't fill a circle with squares because the squares are too pointy! A circle doesn't have any pointy edges, so it's impossible!
We did these math activities several weeks ago by now, but I thought they were worth posting just to see a bit of what we did during the last month of school!
Subtraction Action
First a little subtraction. This is often a hard concept for kindergarteners to grasp, since we spend so much of the year focusing on number sense and then adding together two numbers. But it's important to build a foundation for subtraction, or "taking away," as well.
To begin things we watched some subtraction videos that I found on another teaching blog, including this awesome one that the kids loved, called "When You Subtract with a Pirate."
Then we moved on to telling subtraction stories using dot stickers. I told a story using their names (for example, "Joshua had 10 cookies. His sister ate 6 of them. How many does he have left?") and we depicted it using dot stickers. The kids put actual stickers on their paper, while I drew circles on the SmartBoard. When we subtracted, we crossed off the dots and counted how many were left. Then we wrote and read the accompanying number sentence (in this example, "10 minus 6 equals 4").
We also played some subtraction games, including this fun one called Clear the Deck, which I got from another teacher blog. Each child fills their boat with red chips, then rolls two dice - a plus/minus dice and a number dice. If they get a "minus" and a 5, it means they take off 5 chips. A "plus" means they put more on. The first person to clear their deck wins!
The kids also made up their own subtraction stories to tell others. Here I modeled how to tell a story and draw pictures to help solve it. (Those extremely realistic turtles on a log were actual drawn by me, not a kindergartener.) Then the kids took turns making their own. The story on the bottom goes something like this: "Five flowers were in a field, then three of them got picked. How many were left? They are sad because their flower friends got picked."
Don't Forget about Addition...
We've been touching on addition for much of the year, as soon as most kindergarteners start to get comfortable naming, counting, and manipulating numbers. Here we are reading, writing, and drawing some addition stories (I found the story problems here). This exposed them to a number line, which they will use in math a lot as they get older!
And then Some Geometry
Last but not least, we made 3-D shapes out of marshmallows and toothpicks! Kindergarteners are expected to be familiar with both two- and three-dimensional shapes, including being able to describe and compare them - how many sides do they have? how many vertices ("corners")? how many edges? Building 3-D shapes from toothpicks and marshmallows is a fun and delicious way to study them in depth...
