Science fair projects provide students with an excellent opportunity to gain an understanding of scientific methods while expanding their knowledge through experimentation. They’re particularly beneficial for middle schoolers.
Seventh grade students can easily gain insight into chemistry with this straightforward project that explores the correlation between temperature and chemical reactions. They can complete this experiment within 24 hours for some basic science practice!
Solar Oven
Solar ovens offer an economical and environmentally-friendly method of food preparation that’s utilized worldwide by mountaineers, military personnel and others who must cook outdoors.
The solar oven makes an excellent science fair project for 7th grade students as it allows them to explore multiple physics concepts – heat, reflection, convection and insulation among others.
To make this project successful, you’ll need a box that can reflect sunlight while holding a cooking pot. An ideal choice would be one made out of pizza box material or shoebox material – or similar shapes like these will work.
As well as these components, you will also require a plastic-covered window, some shiny foil and black paper. This will allow your oven to absorb all of the light and heat that enters from outside as it reflects into it from sunlight.
After your solar oven has been assembled, use a small, round object like a wooden skewer to prop its lid at an acute 90-degree angle from its surrounding box – this will enable it to capture more sunlight, thus heating more rapidly.
At the conclusion of your project, you should have an efficient solar oven capable of rapidly heating marshmallows and chocolate. S’mores may take longer to make using such an appliance compared to using traditional stove or oven methods.
Solar ovens can be an indispensable addition to hurricane preparedness kits or situations without electricity, offering safe alternatives to cooking with wood and other fuel sources such as charcoal. Solar ovens make great disaster preparedness options!
Spherification
Spherification is a process used to alter the texture of liquid. While most commonly employed for creating boba tea, this technique can also create gel balls from almost any substance.
This process uses sodium alginate and calcium chloride to create a gel membrane for liquids to be enclosed within. These spheres can be made out of anything from tea leaves, fruit juices or even caviar!
To make spheres, start by mixing calcium chloride and water together, before mixing your chosen liquid with several grams of sodium alginate (C6H9NaO7).
As part of your experiment, select a liquid which is neither too acidic or basic – some examples of such acidic liquids would include soda, tomato juice and red cabbage extract.
Once you’ve selected your liquids, prepare a solution consisting of several grams of calcium chloride in 130 milliliters of water. After mixing this solution, drop each chosen liquid into your bath before rinsing it with more water afterwards to remove any extra calcium chloride.
If you plan on entering this science project into your 7th grade science fair, keep in mind that it can be tricky to get liquids of exactly the right consistency for spherification. Some liquids already contain calcium or potassium ions which will prevent it from working with sodium alginate as intended.
Sequestrants can help remove these ions so your liquids work effectively with gelling agents – you can find these at pharmacies or online.
No matter if it is alcohol, wine or fruit juice that you are spherifying – the end results will always be stunning and this can make an exciting experiment at your 7th grade science fair!
Hydraulic Invention
Hydraulics is a form of technology that uses fluid pressure to produce mechanical force, making hydraulic systems ideal for moving heavy loads or powering machinery. They’re commonly found in cars, trucks and construction equipment as well as household devices like refrigerators or washing machines.
Hydraulic systems traditionally relied on water to drive wheels and levers, but modern systems use other liquids. Oil is an ideal choice as it is non-corrosive and lubricates the system while having greater density than water which enables easier compression of greater power generation.
Hydraulics has its origins in ancient civilizations that needed a way to transport water across vast distances between their cities. As part of these systems, ancient civilisations created complex irrigation systems with canals and aqueducts designed to carry it across long distances between sources in different cities.
Hydraulics remain integral parts of modern life. Everything from office chairs, gas pumps and dishwashers use hydraulic systems that use pressure for their functions.
Early hydraulics largely relied on water and gravity; modern versions, however, utilize various liquids to optimize pressure potential and can range from simple brake pedals to car engines.
Joseph Bramah revolutionized manufacturing when he patented England’s first hydraulic press in 1795, revolutionizing manufacturing practices worldwide. Through Pascal’s law – wherein pressure applied in one area is distributed evenly throughout a system – operators could perform various tasks quickly with minimal investment in mechanical linkages.
Hydraulic systems owe their power and reliability to this core principle, producing even greater force than air or electrical systems. Since fluid leakage can be dangerous, hydraulic systems must be designed for safe operation while still being effective.
Ancient Egyptian Clock
Ancient Egypt’s water clock or “clepsydra” was one of the earliest and most iconic inventions, dating back to around 3500 BCE. The word clepsydra comes from Greek words meaning to steal and water respectively, giving rise to this name.
Egyptologist Ludwig Borchardt asserted in the early 20th century that Egyptian clocks did not work correctly, however Anette Schomberg conducted an intensive research project using 3-D models to demonstrate their accuracy and function correctly and correctly.
These crate-shaped water clocks were intended to regulate the flow of water into or out of containers using capillary action, either using clay or metal construction and following capillary action principles.
Timer clocks were used to indicate hours at night or on days without direct sunlight, as well as being effective sources of water source for use during daylight.
Egyptians were among the first people to utilize sundial clocks, using obelisks with shadow-casting capabilities to calculate time using shadows cast from these towers.
They used sundials to keep an accurate record of when days were longest or shortest throughout the year, as well as portable sundials to be taken with them and used to tell time in various places.
Another great invention for Egyptians was the sickle, used to cut grains such as barley and wheat into manageable chunks for feeding their growing population. This innovation allowed for ample food supplies.
Egyptians developed a civil calendar around 1000 BCE that divided their day into twelve parts, which foreshadowed today’s hour system which changes according to season and length of day.
Slime
Slime is a fun, gooey substance that kids of all ages enjoy playing with. In addition to providing hours of entertaining playtime, slime can also teach students valuable lessons in chemistry.
Simple slime recipes involve mixing borax and glue, though additional ingredients can be added for various flavors ranging from gritty to fluffy, oozing and bubbling, glittery, etc.
Add ingredients that alter its molecular makeup, such as starch. Doing this will cause it to become more solid and less liquid-like – this process is known as cross-linking.
Slime can make for an engaging science fair project while teaching your student more about chemistry! Slime’s fundamental property is an endothermic reaction – which means it absorbs heat instead of giving it off!
Once you’ve created a slime recipe, it is possible to experiment with how it behaves and interacts with different materials – this may involve adding elements like magnets or liquid starch into your recipe to see how they may change its behavior and reactions.
One way of exploring slime is using it as a model for other materials, like paper. This will enable your students to better comprehend how slime forms, what adheres to it, and how different substances can transform into each other over time.
There are plenty of fun slime experiments online, some of which are easy to carry out. One such slime experiment could provide your seventh grade students with an ideal introduction to physical science – they will use the scientific method to experiment on various recipes until one causes specific chemical reactions!