About the author: Jankin, main research direction: Cognitive neuroscience toys are children's good partners, especially STEAM toys, which contain rich knowledge and are a good medium to help children understand the world, learn science, and experience art.

Do you think STEA toys are unfamiliar?

In fact, the balancing birds, roly-polys, slingshots, jigsaw puzzles, etc. that we loved to play when we were children are all among them, and they have also left many beautiful marks in our memories.

Children nowadays seem to have no shortage of toys, from puzzle blocks to cartoon peripherals.

But there is one kind of toy whose status is irreplaceable, and that is the DIY toy. Today we will introduce several interesting and simple handmade STEAM toys.

HnR science category: 1. Bubble bath bombs are so fun and practical, so of course I have to make a few more and put them at home.

Materials needed: citric acid...half cup of baking soda...half cup of cornstarch...half cup of essential oil...appropriate amount (food coloring...optional) water olive oil ball model egg beater or chopsticks bowl how to make

: Prepare two bowls, one large and one small. Pour citric acid, baking soda, and cornstarch into the large bowl, and mix evenly with a whisk; Add one or two drops of essential oil, an appropriate amount of water, and olive oil to the small bowl.

Mix evenly; Slowly pour the liquid in the small bowl into the solids in the large bowl, stirring while pouring; Divide some of the objects in the large bowl into the small bowl, add food coloring, mix thoroughly, and pour it out for later use

.

You can try a few more colors. If you only want to make a white bath bomb, you can go directly to step five.

Pour the prepared mixture (any color combination) into the ball mold, press it tightly, and after five minutes, carefully take it out and let it dry.

*You can make multiple balls at one time.

Principle (Answer to the "why" of curious babies): The main ingredients of bubble bath bombs are baking soda (sodium bicarbonate) and citric acid. The former is an alkali and the latter is an acid. When both are solid, they will not react.

; When both are dissolved in water, a large amount of carbon dioxide gas will be produced, resulting in many bubbles.

Tip: When pressing the mixture with a spherical model, you can add a small object (plastic toy, flower petals, etc.) inside to give the child a small surprise.

2. The principle of the fingertip balancing ball is the same as that of the balancing bird, but it is much more fun to do it yourself.

Materials needed: cork or foam balls, two thin wooden sticks...about 30cm toothpicks, clay or plasticine decorations (colored paper, plastic eyes, paint, etc.) How to make: Pick up the cork and insert a wooden stick into the side of the cork

, so that the bamboo stick and the cork are at a 45° angle; insert another wooden stick on the other side of the cork, opposite the first one, at the same 45° angle; put two pieces of plasticine or clay of the same size,

Glue the other end of the stick; Insert the stick into the bottom of the cork; Use your fingers to hold the stick against the stick to see if the whole device balances. If not, adjust the angle of the stick until it balances.

Decorate the entire installation.

Principle (answer to the curious baby's "why"): Every object has a center of gravity, which changes according to the shape of the object. The weight of clay is greater than that of cork, which makes the center of gravity of the entire device on the wooden stick, so as long as

It is easy to maintain balance when an object drags the stick.

3. A wild brush. The magical little motor is boys’ favorite. Let’s use it to make a wild brush.

Materials needed: Batteries... 4 battery boxes... One (6V) electric motor... One (6V) wire Electrical tape Washers, coins and other flat objects Brush Glue Scissors How to do it: Put the battery into the battery box;

Connect the battery box and motor with wires; Use electrical tape to secure the washers to the motor's rotating pins; Use tape or glue to secure the battery box and motor to the brush; Turn on the switch and watch the brush move on its own!

Principle (Answer to the curious baby’s “why”): The battery provides electrical energy to rotate the motor. When the motor rotates, it drives the washer or coin on its shaft to rotate. The centrifugal force generated by it will make the entire device lose its balance and cause the entire device to vibrate.

Make the brush move.

4. The ancient siege game of pedal catapult began. The second battalion commander quickly pulled out the Italian catapult we made.