This blood model experiment is a great way to get kids to visual what their blood looks like and how complicated it really is. Each ingredient represents a different component of blood (plasma, platelets, red blood cells, etc.), so you just add a certain amount of each to the jar, swirl it around a bit, and you have a model of what your blood looks like.

The best science experiments guide for kids ages 3-9. This is YOUR go-to resource for all things STEM and science all year round!  STEM stands for science, technology, engineering, and math. You can make STEM and science exciting, educational, and inexpensive for young kids. Fun and easy science for kids starts here! Don’t hesitate getting set up for science at home right away.
Be careful: The water only has the power to make the sugar crystals “invisible” when it’s piping hot. After the water cools down and evaporates, the sugar turns back into a solid. And with a little help of your sugar-soaked string, the crystals will find a home to grow upon and become rock candy. Learn how to make your smart sweets with these instructions from the Exploratorium. 
It’s important to get kids involved in science early so they understand the world around them. These science kits focus on critical thinking skills that will give your kid’s hands-on experience to build their curiosity and interest. Help your children discover the fun in learning by checking out these kits that teach them how to conduct their own experiments through the many different fields of science.
Making a borax snowflake is a crystal-growing project that is safe and easy enough for kids. You can make shapes other than snowflakes, and you can color the crystals. As a side note, if you use these as Christmas decorations and store them, the borax is a natural insecticide and will help keep your long-term storage area pest-free. If they develop a white precipitant, you can lightly rinse them (don't dissolve too much crystal). Did I mention the snowflakes sparkle really nicely?
Find out how plants “drink” water with some food coloring. Use carnations, roses, or stalks of celery submerged in the colored water and watch the liquid slowly seep through the plant’s “veins” and towards the leaves. Keep an eye out -- you could have a very colorful bouquet just after the first day. Get the rundown by Dad’s Book of Awesome Science Experiments over here.
You won’t want to do this experiment near anything that’s difficult to clean (outside may be best), but kids will love seeing this “elephant toothpaste” crazily overflowing the bottle and oozing everywhere. Pour the hydrogen peroxide, food coloring, and dishwashing soap into the bottle, and in the cup mix the yeast packet with some warm water for about 30 seconds. Then, add the yeast mixture to the bottle, stand back, and watch the solution become a massive foamy mixture that pours out of the bottle! The “toothpaste” is formed when the yeast removed the oxygen bubbles from the hydrogen peroxide which created foam. This is an exothermic reaction, and it creates heat as well as foam (you can have kids notice that the bottle became warm as the reaction occurred).

There are loads of different science kits to choose from and we know it can be confusing sometimes which types are ideal for younger children to begin experimenting with. Therefore we have picked some really cool experiment kits. In this review, we have reviewed a whopping 32 science kits that stand out as the best overall, so choosing couldn’t be easier. All have an appropriate age guide so you can’t go wrong with picking.
This is an easy and fun kit to learn about science. Got it for a five year old. The concepts are easy to follow and so are the directions. Everything is pretty much provided in the kit in order to make the science experiments with the exception of some ingredients like vinegar or other acidic ingredients that can be easily found in one's pantry or fridge. You will need one paper plate and some Ziploc bags to store the powders provided after opening the package. For example - baking soda. Overall, we've enjoyed this science kit. My five year old asks to make a science experiment each day! Very fun and educational.
a tube, yeast, sugar and warm water, a deflated balloon over the top shake the yeast “farts” which causes the balloon to inflate. I did this at a sleep over with boys 7 to 9 they loved it. you can use an empty water bottle, 1 packet of active yeast, 1/4 cup warm water 1 tsp sugar, large balloon, ruler to measure. measure in 5 min increments. The water wakes the sleeping yeast up. they wake up hungry, you feed them the sugar and their waste/farts are gas that fill the balloon. As they eat the more gas they produce thus filling the balloon. It doesn’t blow all the way up, but it is cool. – Jackie
This Rainbow Skittles science experiment can be done in seconds, making it a great way to try science at home even with the most easily distracted of toddler-sized assistant. All you’ll need to do is arrange Skittles in a circle on a plate and fill the middle with warm water. Then sit back and watch as the colours drain and mix with the water, creating a cool rainbow pattern in front of your eyes. Plus, any bonus Skittles = a tasty treat for you.
This grow-your-own experiment that lets you grow crystals inside an egg shell. Be sure to get alum powder that contains potassium, or else you won't get any crystal growth. Adding drops of food dye to the growing solution yields some super cool crystals. A perfectly formed geode takes about 12-15 hours to grow, making this a great weekend project. Check out more of Art and Soul's gorgeous eggs over at their blog!
Find out how plants “drink” water with some food coloring. Use carnations, roses, or stalks of celery submerged in the colored water and watch the liquid slowly seep through the plant’s “veins” and towards the leaves. Keep an eye out -- you could have a very colorful bouquet just after the first day. Get the rundown by Dad’s Book of Awesome Science Experiments over here.
If your kids are learning about genetics, you can do this edible double helix craft to show them how DNA is formed, what its different parts are, and what it looks like. The licorice will form the sides or backbone of the DNA and each color of marshmallow will represent one of the four chemical bases. Kids will be able to see that only certain chemical bases pair with each other.
There are a lot of science kits for kids out there, so it can be difficult to work out which brands are the best. Some of our favorites for realistic experiments include 4M and National Geographic. For younger kids, the Kids First brand has a lot of good value kits to choose from. The brand Sick Tricks is also a great choice for kids looking to impress their friends or parents with new tricks and experiments. For robotic science kits, Cozmo and LEGO are great options.
The products listed here may contain small parts that are choking hazards for children! Toys can pose a hazard to babies and young children – they can choke, suffocate, or otherwise harm the child. Young children explore their world by putting things in their mouths, but children under three years of age do not have a well-developed coughing reflex and will choke easily on small items. All children, regardless of age, need close supervision with any toys to help prevent accidents from happening. Adult supervision is required at all times! 

These sound like big words for our little ones, but there’s an easier way to break it down. Water and oil won’t mix because they’re not the same “weight” or substance (just like clay and LEGOs won’t become one). Now add a drop of food coloring (which is heavier than oil) and a fizzy tablet and watch the air bubbles take coloring with them to the top. Head on over to S. L. Smith’s blog to see how it’s done.
When a substance passes directly from a solid phase to a gas phase without ever becoming a liquid, it sublimates. Add a little dry ice to bubble solution and the contents of an activated glow stick and get ready to rock the glow-in-the-dark scene in your neighborhood. Owlcation whipped up this awesome experiment to create glowing bubbles, and The Maker Mom thought to add dry ice to the same experiment here. The bubbles are out of this world—they glow and rise from the smoke. Naturally, we recommend an adult to handle the dry ice (skin contact can burn) and supervise this experiment.
By mixing just flour, salt, and water, you’ll create a basic salt dough that’ll harden when baked. You can use this dough to make homemade dinosaur bones and teach kids about paleontology. You can use books or diagrams to learn how different dinosaur bones were shaped, and you can even bury the bones in a sandpit or something similar and then excavate them the way real paleontologists do.
Geode Kits – For any child who thinks rocks are boring – a kit where they can break open their own geode is a great way to change their mind. National Geographic is a great choice if this is the type of kit you are looking for. Their products include hand-picked geodes and come with safety goggles and a stand for your child to proudly display their treasures. A great choice for children aged around 6 years old and above, they’re sure to be more interested in Earth science after this experiment.