October half-term activities to do at home

A sheet of thin paper laid over a leaf, and the long side of a wax crayon rubbed back and forth, brings out the veins. The same trick against a tree trunk captures the ridges of the bark. It takes about 20 minutes and reveals hidden textures. Only pick leaves from plants you recognise, and wash hands afterwards.

A leaf hunt comes first, for dry fallen leaves in different shapes. Each one is painted white with washable paint, given a face in black marker and hung by thread from a twig by a window. Sorting and comparing the leaves helps children aged 4 to 8 name a few trees. Avoid leaves with mould, berries or fungi attached.

Before the pumpkin is scooped out, everyone guesses how many seeds are inside. The seeds are rinsed, tested to see which sink or float, and counted in tens. Ten are saved for planting in spring and the rest are roasted. An adult cuts the lid and handles the oven. Seeds can be a choking hazard for young children.

Four to six cardboard tubes are taped to a large piece of cardboard, each tilted downhill so a marble drops from one into the next and lands in a cup. Testing each slope shows that steeper ramps make the marble go faster. Allow an hour. An adult should help cut the tubes, and marbles need keeping away from under-threes.

Foil pricked with little holes lines the inside of a glass jar, with a battery tea light at the bottom. In a dark room, tiny beams dot the walls with stars, which shows that light travels in straight lines. It suits ages 6 to 11. An adult should make the holes, and a real flame must never be used.

Dots of permanent marker are drawn on white cotton stretched over a plastic cup. A few drops of rubbing alcohol make the colours spread into a starburst, showing how liquids carry colour along fibres. An adult should handle the alcohol in a well-ventilated room, away from faces and flames, and iron the dry fabric to help set the colour.

Two squares of fleece are joined by tying fringe strips together in double knots, then filled with toy stuffing before the last side is knotted shut. No sewing is involved, and the knotting builds neat, patient finger work. An adult cuts the fleece and the fringe, and children do the tying.

Bicarbonate of soda, washing-up liquid and food colouring go into a small bowl or toy cauldron. Pouring in vinegar makes carbon dioxide, which the washing-up liquid traps in bubbles so the potion foams over the edge. It takes 20 minutes and is messy, so use a tray or go outside. Keep faces back when pouring, and nobody drinks it.

Milk or cream, sugar and vanilla are sealed in a small freezer bag inside a larger bag of ice and salt. Five to ten minutes of shaking freezes the mixture, because salt makes ice melt at a colder temperature, pulling heat from the cream. Wrap it in a tea towel, as it gets extremely cold. Check for milk allergies.

Flour, fast-action yeast, sugar, salt, oil and warm water are kneaded inside a sealed freezer bag. The dough is left somewhere warm for about an hour until it doubles in size, because yeast is alive and makes gas as it eats sugar. An adult does all the baking, as the oven and loaf tin get very hot.

The task is to pack a raw egg into a tub or bag with enough padding, such as bubble wrap, cotton wool or scrunched newspaper, to survive a drop. Children aged 8 to 12 predict the result, test it, then add padding or try from higher. It teaches how cushioning slows a fall. An adult supervises every drop.