Count unit squares to find area (K-A)

• Measuring rectangles with different unit squares (K-A)
• Measuring area with partial unit squares (K-A)
• Creating rectangles with a given area 1 (K-A)
• Creating rectangles with a given area 2 (K-A)
• Transitioning from unit squares to area formula (K-A)
• Finding missing side when given area (K-A)