CCSS.MATH.CONTENT.6.G.A.1 Find the area of right triangles, other triangles, special quadrilaterals, and polygons by composing into rectangles or decomposing into triangles and other shapes; apply these techniques in the context of solving real-world and mathematical problems.

Starry Night by Nathan Kraft
Bubble Wrap by Dan Meyer
Dollar Wall by Dan Meyer
Squares Inside Rectangles Prequel by Don Steward (great for practice finding unknown lengths)
Exploring Triangle Area by Michael Fenton, Desmos
Exploring Quadrilateral Area by Michael Fenton, Desmos
Polygons on the Coordinate Plane by Desmos

CCSS.MATH.CONTENT.6.G.A.2 Find the volume of a right rectangular prism with fractional edge lengths by packing it with unit cubes of the appropriate unit fraction edge lengths, and show that the volume is the same as would be found by multiplying the edge lengths of the prism. Apply the formulas V = l w h and V = b h to find volumes of right rectangular prisms with fractional edge lengths in the context of solving real-world and mathematical problems.

Fawn vs Nathan by Mary Bourassa
Banana Bread by Illustrative Mathematics
Computing Volume Progression 1 by Illustrative Mathematics
Computing Volume Progression 2 by Illustrative Mathematics
Computing Volume Progression 3 by Illustrative Mathematics
Computing Volume Progression 4 by Illustrative Mathematics
How Much Money is That? by Robert Kaplinsky
Tricks of the Tray'd by Mathalicious (subscription required)
Ice Cubed by Mathalicious (subscription required)
Cuts, Popcorn, and Clocks - by Fawn Nguyen
Pop Box Design by Timon Piccini
File Cabinet by Andrew Stadel
American Flag, Volume of a Prism by Andrew Stadel
Volume of Rectangular Prisms by Nathan Kraft
Girl Scout Cookies by Dan Meyer

CCSS.MATH.CONTENT.6.G.A.3 Draw polygons in the coordinate plane given coordinates for the vertices; use coordinates to find the length of a side joining points with the same first coordinate or the same second coordinate. Apply these techniques in the context of solving real-world and mathematical problems.

Area of a Quadrilateral on a Coordinate Plane by Open Middle

CCSS.MATH.CONTENT.6.G.A.4 Represent three-dimensional figures using nets made up of rectangles and triangles, and use the nets to find the surface area of these figures. Apply these techniques in the context of solving real-world and mathematical problems.

Candle Box by MARS
Smoothie Box by MARS
Dandy Candies by Dan Meyer
Pop Box Design by Timon Piccini
Area of a Rectangular Prism by Nathan Kraft