What happened in math today?

Here's what I saw when I took a stroll through the elementary math classes today.

Kindergarten - Students sat as a group thinking about, discussing and exploring the idea of attributes. Building on their experiences playing Attribute Castle (a classroom favorite), they took turns identifying attributes about the group (shoes with laces; striped shirts), and then identifying who possessed that attribute and thus fit into the category.

First grade - Students worked on consolidating their understanding of both static (not requiring regrouping) and dynamic (requiring regrouping) subtraction, using one of two tools; some worked with hundreds charts, while others used snap cubes.

Second grade - Students explored the patterns and relationships between the number of sides on a geoblock (triangle, square, rhombus, hexagon, etc) and various number of geoblocks. Understanding that one square will have four sides, and two will have a total of sides, etc, is a precursor to developing multiplicative understanding, very similar to skip counting, and this activity used visual and kinesthetic interaction to reinforce the concept.

Third grade - Students created and identified various types of addition combinations, including "make 10", "doubles", "near 10 (+/-1)", "plus 10", "plus 9", and others. This is a topic begun in kindergarten and usually terminating in third grade, as children's number sense and automaticity allow them to no longer need to count for addition purposes, since the value of single-digit numbers has become internalized.

Fifth grade - Students stood in a circle tossing a ball to each other. When a student caught the ball, she or he had to give an "exit ticket" from class in the form of a combination of various unusual fractions (1/3, 4/7, 3/8, etc) that totaled 1.00.

Unfortunately I didn't stop by the fourth grade class in time to observe!