First day of spring: Saturday, March 20 2021

The vernal equinox - in a given earth hemisphere - northern or southern - is an equinox, after which the sun will illuminate this hemisphere more strongly for half a year and less light on the other hemisphere. The moment of the vernal equinox marks the beginning of the astronomical spring in a given hemisphere, which lasts until the summer solstice.

In the Northern Hemisphere, the Vernal Equinox occurs around March 20/21 (March Equinox) when the Sun passes through the Aries point. In the southern hemisphere, where the seasons are six months shifted, the Spring Equinox occurs on September 22/23 (September equinox). When the vernal equinox occurs in one hemisphere, it is the autumn equinox in the other.

On March 21 in Poland, students celebrate the informal truant's day. Some school authorities try to limit or legalize truancy on this day by organizing school events and occasional trips (e.g. to the nearest park to celebrate the first day of spring, in the form of traditional melting of Marzanna - a symbol of the passing winter).

A little laughter won't hurt. :)