Click on the link below for the "2-58 Student eTool" (CPM).
1. The user can:
- Drag tiles from the tray to the Display area.
- Click tiles to change color to black.
- Drag a textbox to the display area to label or explain.

2. Build the expressions by:
- Displaying the correct number of positive and negative tiles.
- Clicking tiles which result in a value of 0 turning them black.
- Using a textbox to write the answer.
