The invention of the calendar is a remarkable event for humanity. The fact that a year consists of 12 months is no secret to anyone.

Since then, people have grouped 12 months into calendars in a variety of ways.

This little "joke" task will keep your kids (students) busy for a while!

What plastic tetrahedron* needs to be melted to cast a cube with an edge length of 50 mm from this plastic?

If you don't like math, then on Halloween, evil forces will come for you! Create two guards who will protect you from evil forces! Well, or, be ready for the math exam….

The Great Archimedes is ready to help us.

And it's great! According to legends, Archimedes created amazing structures to defend Syracuse's hometown in the battle with the Roman Empire.

Find a gift for the schoolboy that will be interesting, useful, and not ruin the family budget - is this possible in 2020? We tell you how to please and surprise modern demanding children?