Can index cards hold a book? This is a great beginning of the year STEM Challenge...or any time of year...to get your learners going through the Engineering by Design Process and practicing the 4C's. In this STEM Challenge, learners try to hold up a book or books with just index cards. Learners take a look at different shapes in architecture. You can discuss the difference in 2D and 3D shapes. Learners can discuss which shape they think is the strongest and why. Google Slides take you and