Species name: Ranunculus acris
Location: Eurasia, parts of North America. Seen frequently in grasses/fields and sometimes paths
Symbolism: Joy, youth, childishness, humility, etc.
Notes:
Toxic when ingested and considered a weed in some places. The pollen can get all over your fingers pretty easily.
Can grow abundantly in rarely-maintained school grass fields during early spring and summer.
It's easy to put into someone's hair.