# Algebraic Thinking

### Parentheses: How big of a change can they make!?

Once students understand the order of operations, they often just get stuck doing increasingly difficult practice problems. That's a sure-fire way to squelch learning, though. Here, students determine where to place parentheses to make the greatest change in an expression.

### Undoing Multiplication With Division

Multiplication and division, natural foes, are constantly seeking to undo each other. Students will attempt to reverse the effects of multiplication by dividing once, twice, or even thrice!

### Factors and Codes

Let's use factors to encode and decode words.

### A Calendar Math Project

Why are there 12 months? Why don't weeks fit into months evenly? Why don't weeks fit into the year evenly? What's going on with the calendar!

### Doubling Dollars

Say you have a dollar. Say you can double that dollar each day: \$1, \$2, \$4, and so on. How long will it take to reach… one million dollars? Not as long as you might think!

### How Many Will There Be? Desks

Give kids a taste of a sequence, let them build an understanding, and then see how far their predictions can take them.

### How Many Will There Be? Pyramids

Give kids a taste of a sequence, let them build an understanding, and then see how far their predictions can take them.

### How Many Will There Be? Chip Off The Block

Give kids a taste of a sequence, let them build an understanding, and then see how far their predictions can take them.

### How Many Will There Be? Stairs

Give kids a taste of a sequence, let them build an understanding, and then see how far their predictions can take them.

### How Many Will There Be? Flowers

These flowers sure are getting bigger faster! How large will they be in step 10? What about step 50?

### How Many Will There Be? Sliced Circles

Give kids a taste of a sequence, let them build an understanding, and then see how far their predictions can take them.

### Factors and Codes 2: First Names

Scrambled up somewhere in 161,000 is a first name. Can you find it!?

### How Many Will There Be? Triangles Within Triangles

A triangle splits and splits and splits again. How many will there be in step 20?

### How Many Will There Be? Courtyard

Give kids a taste of a sequence, let them build an understanding, and then see how far their predictions can take them.

### How Many Will There Be? Xs and Os

Give kids a taste of a sequence, let them build an understanding, and then see how far their predictions can take them.

### How Many Will There Be? Earthworm

Give kids a taste of a sequence, let them build an understanding, and then see how far their predictions can take them.

### How Many Will There Be? Squares in Squares

Give kids a taste of a sequence, let them build an understanding, and then see how far their predictions can take them.

### How Many Will There Be? Checkerboard

Give kids a taste of a sequence, let them build an understanding, and then see how far their predictions can take them.

### How Many Will There Be? Crosses

Give kids a taste of a sequence, let them build an understanding, and then see how far their predictions can take them.