Tinker Crate develops kids' natural creativity and curiosity using STEM ("Science, Technology, Engineering, and Math") principles while saving time for busy parents. Our mission is to help kids use STEM as a key to creative problem solving, a foundation for critical thinking, and a pipeline to innovation. Your monthly crate includes all the materials and inspiration for science and engineering projects such as: trebuchet, paper circuits and zoetrope.

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.
For this saltwater density experiment, you’ll fill four clear glasses with water, then add salt to one glass, sugar to one glass, and baking soda to one glass, leaving one glass with just water. Then, float small plastic pieces or grapes in each of the glasses and observe whether they float or not. Saltwater is denser than freshwater, which means some objects may float in saltwater that would sink in freshwater. You can use this experiment to teach kids about the ocean and other bodies of saltwater, such as the Dead Sea, which is so salty people can easily float on top of it.
How are some dinosaur tracks still visible millions of years later? By mixing together several ingredients, you’ll get a claylike mixture you can press your hands/feet or dinosaur models into to make dinosaur track imprints. The mixture will harden and the imprints will remain, showing kids how dinosaur (and early human) tracks can stay in rock for such a long period of time. 

Chemistry Kits – Perhaps the most classic of the science kit options, these are great for kids who are interested in learning about how things work. There is a huge range of kits in this bracket, ranging in features and suitability. There is a chemistry kit for just about any child, and with a bit of research it’s easy to find one to suit your child’s age and ability.
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!
My First Mind Blowing Science Kit also comes with cool scientific tools like test tubes, pipettes, stirring sticks, and measuring scoops that will make your child feel like a real chemist. Not only will they learn important skills in conducting experiments, they will also learn the basics of acids and bases. While none of the experiments are particularly messy, it’s safer to perform them on a flat surface with adult supervision.