Solar System scale activity

In 2014-04, I was asked by Sagamore second grade teacher Ms. Quinn to help do something for the first grade and kindergarteners on Sagamore Space Day. I'd like to do what I proposed back in January, of imagining the real scale of the solor system, riffing off of, "How Big is the Solar System? | It's Okay to be Smart | PBS Digital Studios - YouTube".

The longest length of the Sagamore field is 480 ft

I'm using an online solar system scale calculator to see what our solar system model can look like. Although the video serves science education by using metric units, I wonder if we should use US customary units instead? Using the scale chosen in the video, 1,264,000,000:1 (calculated from the video's stated 110 cm (4.3 inch) grapefruit = 1.39 million kilometer sun)!, we can comfortably get out to Saturn at 370′. A 5.5′ sun gets us Saturn at 470′ (the length of our field) and a scale of 1,600,200,000:1 , but I think I'll stick with their scale because they give us good size references (e.g. Mercury is only the width of just 4 human hairs).

Solar System at
1/1,264,000,000 Scale

What	Diameter	Orbit Radius (feet)	Difference from Prior (feet)
Sun	Grapefruit (4.3″)
Mercury	4 hair widths (0.0151″)	15
Venus	10 sheets of paper thick (0.0376″)	28	13
Earth	1 millimeter (0.0396″)	39	11
Mars	½ the size of Earth (½mm) (0.021″)	59	20
Jupiter	Almost half-inch (0.4448″)	202	143
Saturn	Hieght of Lego brick (0.3622″)	370	168
Uranus	0.146″	744	374
Neptune	0.1413″	1,167	423
Voyager spacecraft (farthest man-made object)		4,590 (0.87 miles)
Betelgeuse (Red giant star)	135′
Sirius B (White dwarf star)	0.0433″

What	Distance from Sun (miles)
Alpha Centauri (Nearest star)	2,000
Galactic center (Center of Milky Way)	12,873,222

What	Quantity
Light Speed	1 inch per second
Light Year	465 miles

Activity

I imagine taking kids out to the field, starting in the eastern corner, and explaining the concept of scale. Out comes the (grapefruit?) Sun and a bags of little objects. Invite them to choose the right size objects and place them around the Sun, at the same kind of distance the planets really are from the Sun (to scale).

Establish a foot by measuring the leaders foot and deciding how they'll walk to measure out feet.

The leader will have their own bag of planets to scale, taped to flags to be planted.

Then the distance is correct distance is shared, and the group counts out he paces. The true model planet is revealed, a factoid is shared; imaginations are challenged. Repeat up to Saturn (when room is run out).

I know it might be hard to keep all kids engaged. But, it's outside, they get to run around a bit and count out paces, and I think seeing how tiny the planets actually are and how far away everything is, can impart a real impression of the reality of space.