Old mason jars + old window screen= firefly jars!
I used old canning jars with rusty seals as a way to recycle. I spray painted my rings to make them look clean and finished. On new jars you can skip this step.
Remove the flat seal out of the ring. You won't need this. Spray paint your ring if you like. If you're making jars for multiple kids think about using different colors of paint.
Trace the flat seal onto your window screen with the marker.
Use tin snips or old scissors to cut out your rounds of screen. Wear safety glasses, the screen bits can get in your eye when you cut it. Ouch! I will not be getting the blame for your new eye patch.
Place screen rounds into ring to check for fit. I put the lid on my jar and screwed it down to try to bend any extra screen into a better fit.
Use hot glue to tack the screen into the ring. It doesn't have to be perfect, this is just to make sure it doesn't fall out & get lost when opening the jar in the dark to add bugs.
Add the screen back into the ring over the glue & use the end of something besides your finger to press it into place. I'm not taking the blame for your new finger bandage that matches your eye patch.
You're all done! Go explore nature and catch some bugs! Don't be a bug murderer, let your specimens go at the end of the night, please and thank you!