Area & A Mathematical Milestone

This week, we started our first geometry unit, Area.

We've learned that area is the number of units needed to cover a shape.  Since square units are easiest to cover most shapes and count,  we usually use these to measure a shape's area.

Today we broke out the GeoBoards and learned how to use them as tools for modeling area and other two-dimensional shapes.

(First, we had 5 minutes to "explore" our new tools, be creative, and use them as toys.  Naturally, this lead to a nice review/discussion about symmetry!)

Next, we made a grid on the GeoBoards and found out each board has an area of 16 square units.

From their work with arrays in third and fourth grades, the students have realized they don't need to count squares for rectangles one by one. (Yes, a square is a rectangle!)  Instead, we can multiply the dimensions (number of rows times number of squares in each row).  Knowing this, the students learned their first mathematical formula:

Area of a rectangle = Length x Width

Then we practiced making shapes with a given area--2 square units, 3 square units, and 6 square units.

Some students remembered from third/fourth grade fractions that two triangles are equivalent to one square unit of area and used them in their designs.

I don't even think some of the students realized it was raining outside and recess time.  :-)