Luke,
you can find a few ways to create a scale model of the solar system using the Solar System resource from spaceweek.ie, in English or Irish.
With a very young class, I’d just concentrate on relative sizes and the related language of big, bigger, biggest. Even for an older class, I’d determine a suitable scale for the size available.
The solar system is remarkably empty, so most scale models have to be over a very large space to get a sense of the distance to the furthest planets, or else the inner planets are almost all on top of each other.