What you need:
A plate, a glass jar with a broad mouth, a tissue, a piece of paper, water and a matchbox
What to do:
1. Make the tissue paper wet and lay it out on the plate. The tissue should be broader than the mouth of the glass jar.
2. Cut the paper into a strip the size of a sticky note.
3. With an adults help, set one end of the paper on fire and drop it in the glass jar.
4. Check that the paper is burning well inside the jar and then quickly invert the jar over the wet tissue on the plate.
5. Let the paper bum and go out. Once that happens, try to lift the jar.
The entire plate comes away with the glass jar
The burning strip of paper heats the air inside the jar, causing it to expand and leave the jar. When you invert the jar on the plate, and the paper goes out the air inside the jar cools and contracts, causing the air pressure to fall. Normally, air from the outside would rush in to fill the extra space left by the contracting air. But the plate and the wet tissue are in the way this time. So there's a low air pressure zone inside the jar while the air pressure outside it is higher. Due to this pressure difference the air pressure outside pushes the plate against the jar, causing the two to stick. They remain like this as long as the tissue is wet, because the wet tissue essentially acts as a seal that doesn't allow air to pass. However, once the tissue dries... crash!
Picture Credit : Google