The kids played the marble game in the playground, seeing whose aggies could roll the farthest.

aggies 是 agate 的昵称形式，agate 本意是"玛瑙"，这里指用玛瑙制成的弹珠。在弹珠游戏中，aggies 特指那些用半宝石材料制作的弹珠，通常比其他普通弹珠更珍贵。