We are continuing our unit study by weighing and balancing rocks and minerals on precise balance scales. Balance (or a pair of scales) uses a balance beam and compares masses by balancing the weight due to the mass of an object against the weight of a known mass or masses. Today, Adrian compares masses by balancing the weight of an object against the weight of a known mass (i.e. metal weights with its mass stated on them), and he also compares masses by balancing the weight of minerals and rocks against the weight of an unknown mass: e.i. other mineral or rock on the other side of the scale. This activity is also a fun way to introduce fact families: for example 50 gr on one side equals to 20+10+10+5+5 gr.

There are variations you can do with your child while using balance scales:

[AGE 1Y+] discuss heavy (rock) vs light (feather)
[AGE 2Y+] try to balance common objects: e.i. nature finds such as leaves, flowers, acorns or pinecones, toys, or even food; the goal is to figure out how objects of unknown mass weight (anything other than metal weights) can come to the equilibrium by having the scale precisely balanced
[AGE 4Y+] invite your child to determine the actual weight by adding the value of metal weights balanced to equilibrium on the other side.

These scales are also perfect for weighing Geodes which are hollow and thus light in mass as compared to a regular stone or rock. Geodes are rounded hollow voids in rocks filled with crystals and other minerals. They are typically formed when air bubbles inside of volcanic rock form hollow cavities. Over time, as mineral-rich water seeps into the rock it beings to deposit tiny crystals on the sides the hollow cavity.

You can see this activity on Instagram here.

P.S. Always supervise your children while they are exploring through play, Xoxo

For more hands-on activities, please see here A Closer Look at Rocks and Minerals Unit Study.

For more weighing and balancing activities, please see here Fall Inspired Weighing Activity with โ๏ธ Balance Scales.