We used butterflies as a jumping off point for looking at lines of symmetry.
We began by using this butterfly matching game to reinforce the concept that butterflies wings are symmetrical.
Next, we used some really simple ideas for our loose parts center:
We put a stick in the middle of the cork board that we use with our loose parts, and let the students make their own symmetrical images (these two decided to make butterflies with the shape buttons and sticks)
Another simple idea: tangrams and a piece of tape:
I put a piece of masking tape on the table and a bin of tangrams out. I was really impressed with all the designs that they came up with.
Here is a last one for you, this one involves using a light table, but could be used on any surface also.
We laid out two different kinds of gems and some sticks. The students were excited to use these materials in a different way, and used them to create some symmetrical images.
There you have it, 4 ideas on how to practice symmetry in kindergarten using materials that you probably already have!