Fingerprints; invisible ink; writing on one skin; x-rays.
putting up a hook with a suction cup or adhesive backing; important concepts how to work with a broken window;
Understanding the Concept of Creating Musical Sounds on Shabbos;
The Importance of Dipping the Vegetable into the Salt One Piece at a Time: Is One Allowed to Use Other Spices (e.g., Pepper, Paprika,...