continue...What should I pack for the weekend?
... you can pack everything you need without worrying
that "it will be heavy". If you are complete beginners, basic equipment is sufficient; no special gadgets are needed.
As for clothing, more versatile items work great (Rab Borealis). It works well for hiking, cross-country skiing, running, or cycling trips.
The absolute basics of such a gear list include a merino shirt, so you can wear one shirt for two days without it smelling, and good socks that won't give you blisters. Another item is a poncho or waterproof jacket to keep you dry during a downpour. You can also try switching to running shoes instead of hiking boots for the first time to strengthen your legs. Or you can try filtering water without your life depending on it. For more experienced hikers, weekend trips give them a chance to experiment with very minimal equipment such as a tarp/poncho (SMD Gatewood Cape) and explore the advantages and disadvantages. You can try going with a really small, ultralight backpack (Gossamer Gear Kumo), or don't bother cooking and try eating only cold, soaked food (known as "cold soaking") in the morning and evening.
It's also an opportunity to try out what it's like to hike in all-day rain without any consequences, or to test how many kilometers you can cover in two days. These are all experiences that will come in very handy on longer trails like Stezka Českem, or Pacific Crest Trail (PCT).