Models Showcase

Print one at 205 mm and four at 100 mm (change the width); the four small trays tile the big one, two of them flipped over. Prints as shown on its outline, no supports.

Slide the phone in face up through the slot, stretch cling film drum-tight over the top and sprinkle a pinch of salt on it. Prints as shown on its floor, no supports.

Wind about 60 turns of 0.3 mm enamelled wire on the tube; use a 1N34A germanium diode, a crystal earpiece, 20 m of aerial wire and a ground to a metal water pipe. Prints as shown on its floor, no supports.

Print four. Arrange them in a square with the notches facing the middle. Prints as shown on its outline, no supports.

Stand the cells in a tray with an air gap underneath; water a little more often than solid pots. Prints as shown on its floor, no supports.

It is 240 mm tall, so lower the height on a smaller printer. Bury the bottom half in the bed so the side windows are under the soil, add a handful of compost worms, and feed scraps through the lid. Prints as shown on its floor, no supports. Large holes in the walls may need supports or good bridging. The lid prints as a separate part, top down.

You need dish soap, salt, a coffee filter and ice-cold rubbing alcohol (adults handle the alcohol). Strawberries have 8 copies of each chromosome, so they give a lot of DNA. Prints as shown on its floor, no supports.

Cut matchsticks or cocktail sticks to 40 mm, the same as the line spacing. Drop them from 20 cm, about 20 at a time. Prints as shown on its floor, no supports.

Every part prints flat: screw the column into the dish and the cup onto the column. A smaller marble or a shallower cup makes it more sensitive. Prints as shown on its floor, no supports. Stacked parts are fused into one print.

Hide a sweet (the car) in one box and nothing (the goats) in the other two. Play 20 rounds sticking and 20 switching, and keep score. Prints as shown on its floor, no supports. The lid prints as a separate part, top down. The added bases' lids print separately.