When a Line Bends

It's just about time to change our bulletin board again and I realized that I never posted our Shape Posters.  I put together this bulletin board at the end of our Geometry Unit.  We titled the board "When a Line Bends.... A Shape Begins," which comes from title of a book we read during this unit. Our Art Teacher actually uses this book to start off some of her art classes so a lot of the other classes were excited to see the phrase on our board too.

I used this board to display the shape posters that the kiddos made in math.  After we had spent a while identifying determining features of shapes,  the kiddos got to create posters to show what they had learned.  They had to work with a partner to sort a set of shapes into logical groups. They were allowed to choose how they would sort their shapes so this was a good way for me to see how well the kids understood the properties of the shapes. A lot of the kiddos used the idea of "round" or "curved" sides versus straight sides to sort their shapes.  A few partnerships grouped the shapes by the number of sides.

I think the board turned out pretty cute and the kiddos loved seeing each other's posters.  Next week we will have a new board though, in preparation for our Social Studies Exhibit.

3D Shapes

One of my brothers is currently in graduate school, studying math at Penn State.  This weekend, I was home in PA with my family, and he was filling us in on his first few weeks of teaching a vector calculous class.  He told me how, during the first class, he challenged his students to draw a shape in 3D to point out that there are multiple ways to see a shape.  Wow, I just taught the same lesson to my kiddos!  Obviously, we had different intentions but still, it's pretty cool.

We just finished our Geometry unit in first grade.  I rearranged the units slightly so that we could do 2D and 3D shapes at the same time.  As I posted about a few weeks ago, this unit had a lots of "ah-ha!" discovery moments as the kiddos learned to see and understand shapes in new ways.  We started out introducing 3D shapes by having the kiddos examine the "footprints" of different blocks.  They were shocked to discover that a pyramid actually has one face that is a square.  Even more surprising was that a ramp block, has one face that is a rectangle.

After the kiddos had a fairly solid grasp on this idea, I asked them to attempt to draw a block in 3D.  This had some fascinating results.  Some kiddos drew the base, sides, and top all stacked on top of each other; others drew the faces of the shape in a row; others drew slanted lines to show perspective.  This lesson was also very frustrating for many of my little guys, because while they know what they want to draw, they can't figure out how to make it on the paper.  We talked about some traditional ways to draw 3D shapes and also tried to explain that there is no "one right way."

The next step of the lesson was to attempt to draw a building of 3D blocks.  This was also an interesting and often frustrating task for the kiddos.  They struggled to figure out how to show depth, angles, and height.  After they had something on paper, I had them switch with a peer and try to create the building they saw on paper.  This really showed them the importance of accuracy and perspective. As a class, we discussed the challenges of this activity and why it was valuable to learn from both our success and mistakes in drawing 3D shapes.

Next week, we are back to focusing on addition and introducing subtraction.  Let's see how that goes!

Geometry

More math...

Investigations has two units on geometry to first grade but this year I decided to combine them into one unit that will cover both 2D and 3D shapes.  So far the first part of the unit is going really well.  Most of my kiddos came into first with a strong knowledge of shapes.  They could name the basic shapes (circle, square, triangle) and define simple attributes about them.

Therefore, I have been working to introduce new vocabulary to describe shapes (vertices, polygons), and also challenge their thinking about what defines a shape.  On Friday, we had a great discussion regarding what defines a "quadrilateral."  I introduced the word and explained that quadrilaterals are 4-sided shapes with 4-corners, or vertices.  I asked the kiddos to name some quadrilaterals and, not surprisingly, they came up with square, rectangle, diamond (or rhombus), and trapezoid.  Then I sent them back to their seats to explore with geoboards.  As the kids were making shapes, I took some pictures and put them up on the SMART board for our discussion.

During our discussion at the end of the lesson, I asked the kids if they thought these shapes were quadrilaterals.  Although of course they are, this is a challenging concept for first graders to accept.  We talked about the characteristics of quadrilaterals and checked the shapes on the board.  The looks on the their faces when I explained that all of the shapes we'd seen were quadrilaterals were priceless!  It's so exciting to see them make this kind of mental breakthrough in their understanding.  I'm looking forward to the next part of the unit which focuses on 3D shapes because I know our discussions will continue to be lively and informative.