Simple credit card size card that has a 1, 3, 5, 7, 10mm pin-hole to see the affect the eclipse has on the projection.
This should be used to allow the sun light to pass through the pin-hole and see the eclipse effect as a projection. Your back should always be to the Sun when using a pinhole projector. Do NOT look at the Sun through the pinhole!
https://science.nasa.gov/wp-content/uploads/2024/01/2024-total-solar-eclipse-pinhole-projector-activity.pdf