Traffic light

Did you know the first traffic light actually exploded injuring its operator?

The first traffic light ever was installed on December 9, 1968 in London outside the House of Parliament to control the traffic in the nearby three streets.

Based on all the future developments, traffic lights can be classified in various ways.

Traffic light

Traffic light

Classification on the basis of the automation of traffic lights:

There are two categories of traffic control system: A fixed system and a dynamic one. The dynamic traffic control systems can be further classified based on the types of detectors used in them.

The fixed traffic light control system is configured to switch lights after a certain period of time. The time interval depends on the region and traffic values. It has a controller that moves with dial timers to be able to display a certain color for a small interval of time.

Dynamic traffic control systems, on the other hand, are more appropriate as they are able to adapt their settings according to the crowd present at different times of day.

When a car passes over the Embedded Detector, it simply sends the information to the traffic light. In this way, the traffic system which can already control the timing by itself, knows for sure that there’s a line of cars waiting for the signal to go green. This kind of detector is generally expensive due to its cost installation and maintenance.

Mounted Detectors are quite affordable and its installation is not affected by any other systems located in its proximity. Not only these are inexpensive, but they also send over more information to the traffic lights which include real-time photos.

Classification on the basis of the use of a traffic signal

Let’s look at the following categories:

Junction Signal:

This signal control vehicles coming towards a certain junction in a contradictory manner. With the help of a camera mounted on it, it monitors and responds to the flow of traffic, whether heavy or light.


It facilitates the street crossing for people. This signal displays a digital dotted green-man signal or a red-man signal crossing for a fixed interval of time. Hence, it indicates for common people, according to its color, when it is safe to cross the street and when not.


This signal controls a shared crossing for common people and cyclists. It is usually wider than the Pelican Crossing mentioned above. It has standard red/green/yellow signals with a green digital cycle next to the man hence controlling the traffic of both of them (Cyclists and Pedestrians) at the same time. When the Toucan is busy, detectors help it by increasing the crossing time.

Equestrian Crossing:

This is mainly used by horse riders and more than often referred to as Pegasus crossing. Red and green horse signal display helps the riders to know when you can cross the street and when not.


Last, but not least, this is the one we all are very familiar with. It is again a pedestrian crossing facility. This mostly works in combination to the traffic light. When a pedestrian steps on to this area, a motorist has to give way. This crossing also has orange flashing light at both its end to indicate the presence of the crossing.

Zebra crossing

Zebra crossing

Traffic Signal Color Coding:

Red was the color that denoted blood and thus it was selected to stop the vehicles. It became the symbol of danger. Also, even in misty environment, red color could be seen from far distance and hence avoided fatal collisions.

Green symbolizing nature was chosen as signal for relaxing as observed by human emotions. And it was clearly visible at the night time and since it is quite a contrast in comparison to red and yellow, it would never create confusion for the drivers.

As for Yellow, most people believe that it symbolizes sun and is taken as a sign of caution.

Over the years, traffic lights have evolved although maintaining the basic colors to accommodate people suffering from color blindness. Red-green color blindness, these days, is the most common form of visual impairment. Hence the red light comes with a little orange and green comes with a little blue to address this socio-medical issue.

We can conclude that traffic lights were a great invention for all of us. But what if I tell you can build one too? That way you could teach him about this simple invention that we use in our day to day lives. Don’t worry; you can get the raw materials from Projects For School-Traffic light DIY Kit. If you are a parent who believes in “Practical is always better than just theory “then this is the ‘go to’ place for you.  Explore it. You just might find a great science project for your kids this semester!




10 most important inventions in physics

Students often complain that Physics is a tough subject. However, physics has also led to some very significant and interesting best science projects experiments, discoveries, inventions and changes in human life. Here is a brief list of some of 10 most important inventions in physics.

  1. The Wheel

The difficult part of the wheel was connecting a wooden platform to it. “The stroke of brilliance was the wheel-and-axle concept,” says David Anthony, a professor of anthropology at Hartwick College. Wheeled carts facilitated agriculture and commerce by the transportation of goods to and from markets.

The Wheel

The Wheel

  1. The Compass

Ancient sailors navigated by the stars, but that didn’t work during the day or on cloudy nights making voyage unsafe. The Chinese invented the first compass. Soon after, the technology passed to Europeans and Arabs. This is one of the best  science projects that had enabled mariners to navigate safely far from land. It increased sea trade and made the lands richer.

The Compass

The Compass

  1. The Printing Press

Though inventors in China and Korea had developed movable metal type, Gutenberg was the first to create a mechanized process that transferred the ink from the movable type to paper. Printing books and manuscripts became faster and led to widespread dissemination of knowledge for the first time in history.

The Printing Press

The Printing Press

  1. The Internal Combustion Engine

In the internal combustion engine, the combustion of a fuel releases a high-temperature gas, which expands, applying a force to a piston, moving it in the opposite direction. Thus, combustion engines convert chemical energy into mechanical energy. The engine welcomed the Industrial Age!

The Internal Combustion Engine

The Internal Combustion Engine

  1. The Telephone

Alexander Graham Bell was the first to be awarded a patent for the electric telephone in 1876. He called it an “electrical speech machine.”The invention of this best science projects of all time  quickly revolutionized global business and communication. When Bell died on August 2, 1922 U.S. telephone service stopped for a minute to honour him.

The Telephone

The Telephone

  1. The Archimedes’ Screw

Archimedes’ greatest invention which is one of the best science projects in physics is the Archimedean Screw. He probably invented this device when he visited Egypt, where it’s still used for irrigation. The screw can be used for lifting finely divided solids.

The Archimedes Screw

The Archimedes Screw

  1. AC current

Tesla’s most important contribution to energy history is the use of alternating current (AC). The technology became the basis for most modern electricity distribution systems.

AC Current

AC Current

  1. Superconductors

Superconductivity is a phenomenon of exactly zero electrical resistance which allows current to flow through a certain materials when cooled below the critical temperature. Can you imagine current flowing indefinitely through a wire? All our electricity woes will end by perfecting this technology.



  1. Nuclear technology

Nuclear technology is technology that involves the reactions of atomic nuclear. Notable nuclear technologies include nuclear reactors and nuclear weapons. Though nuclear bombs have not made the world any safer, but this nuclear technology, one of the best science projects discovery is not all bad.

Nuclear Technology

Nuclear Technology


  1. X-rays

Wilhelm Röntgen received the very first Nobel Prize in Physics in 1901 for his best science projects discovery that is  X-rays. Within two weeks of generating X-rays he invented X-ray photography. The first ever X-ray photograph was of the bones in his wife’s hand.



We love to assist our visitors, students, parents in their quest to learn science, you are welcome to leave your questions / comments. Chat with us, use contact us from here or on our facebook page ( In conclusion, drop us an email for any other queries and we would certainly reply with an answer to your queries!!

Angry Teenagers (Dealing with your child’s anger issues)

Angry Teenagers – Channelizing it

through activities 

When your teen is angry and screaming at you, it is very tempting to scream louder so you “win” the argument. But what does that do? In addition to prolonging the argument yelling back also means that you’re giving up your power. Giving in to the temptation can be quite costly in ways you probably didn’t realize. When you yell at your child, it simply escalates the argument and it turns him into an angry teenager.

Angry Teenagers (Dealing with your child's anger issues)

Angry Teenagers (Dealing with your child’s anger issues)

What not to do

  • Curse or name-call:  

    There’s no excuse for abuse—not by your child and not by you. Being verbally abusive to your child only makes things worse, both in the short-term when the argument escalates, and in the long-term when your relationship with your child becomes strained.

  • Attempt to control that angry teenager:

    This is one of the biggest stumbling blocks for parents. We hear from parents every day who, without realizing it, are trying to control their children. Holding your child accountable does not result in a child who is obedient all the time. Accountability means that you set the rules and you provide a consequence when your child decides to break the rules. You’re not a puppeteer; you’re a limit-setter. Let your child make his own choice. When a child experiences this unpleasant outcome, he can use that information to help him think about things next time he is considering breaking the rules.

  • Get physical:  

    A beating is not the way a teen will learn to do the right things. Often parents beat their children to the extent that they simply become immune to the punishment. In other cases, teens can be severely affected emotionally by it. Fear can set inside their mind.

Angry Teenager

Angry Teenager

What to Do

  • Walk away and calm down:  

    Ask yourself if the issue needs to be dealt with right now? Should you take some time to calm down before you address it with your child? Think about the situation carefully and allow things to cool down. You can address it later if you still feel the issue is important after you’ve thought it through. Teach your child the same technique.

  • Use a business-like tone:  

    When things are turbulent, address your child in the same tone with which a professionally-mannered boss would address an employee with poor performance. Stay calm and neutral, and stick to the facts.

  • Be honest:  

    Let your child know you’re having a hard time communicating with them when they fly into a rage. It’s perfectly okay to say things like, “When you scream at me, it doesn’t help any of us.”  This is a simple way to let them know their behavior isn’t working.

  • Channelize anger:Get your teen to work on different projects for school. Anger can be easily controlled with some constructive distractions like projects for school. Here at Projects for School, India, we have many science project kits which will help children educationally. Projects for School aims to provide children with educational and fun projects which will help channelize their energy in the right direction.
Angry Teenager

Angry Teenager

Visit and choose from among a wide range of science kits.

We love to assist our visitors, students, parents in their quest to learn science, you are welcome to leave your questions / comments. Chat with us, use contact us from here or on our facebook page ( In conclusion, drop us an email for any other queries and we would certainly reply with an answer to your queries!!


Alarms and it’s types 

               Alarms are used to alert people to potential danger. However, they are useless if people don’t recognize the alarm and know what it means. They should know how to respond to a particular alarm. Whether it is a family function, a school, or a place of business, an alarm should be in place to alert people. These days, most alarms are electronic in nature and it helps to understand their components and functionality. In this article we will look at that and also some types of alarms.

Components of alarms:

Electronic alarm systems are made up of components designed to detect, determine and deter threatening situations.

  • Motion Sensors:

    They can detect movement in a room or a corridor.


Motion Sensors

  • Glass Break Detectors:

    They are designed to constantly listen for the sound of breaking glass. When it detects the sound pattern caused by shattering glass, it sends an electronic signal to the alarm control panel.


Glass Break Detectors

  • Shock Sensors:

    They can detect an intruder who is using force to pound through a wall or any area of a structure.


Shock Sensors

  • Keypad:

    Keypad is used to arm and disarm an alarm system. They are generally installed near the entrance or exit of a building.




  1. Carbon Monoxide Alarms

Carbon monoxide is an odourless, invisible gas that can lead to poisoning. These alarms use electro-chemical sensing technology to alert you.

  1. Burglary

A thief breaks the glass of your shop! Instantly a high pitched wail sounds in the air! Almost every house or shop abroad has burglar alarms. Unfortunately, the practise is not very common here in India.

  1. Fire

Smoke and fire alarms warn people of the presence of fire in a building. Some alarms have the feature of alerting the nearest fire department. Many places, such as schools and college dormitories, perform drills to practice what to do in case of a fire alarm.

  1. Flood

It has nothing to do with warning you of the infamous Mumbai floods. Water damage from a faulty water heater can be just as damaging to a home as a fire. Flood alarms sense the presence of water and can be programmed to shut the water off when it is nearing a flood zone.

  1. Weather Alarms

U.S faces tornadoes, hurricanes and horrific forest fires every year. It is extremely important to be able to recognize alarms that warn of severe weather. Many cities have public alarm systems that sound informing people to take shelter. The National Weather Service issues severe weather warnings through television and radio broadcasting systems.

        We’ve all seen Charlie’s Angels break into top security vaults and moving out with groundbreaking pieces of technology. They protect our life and our property! How about trying this simple circuit diagram of an alarm available as DIY science project for alarms at

We love to assist our visitors, students, parents in their quest to learn science, you are welcome to leave your questions / comments. Chat with us, use contact us from here or on our facebook page ( In conclusion, drop us an email for any other queries and we would certainly reply with an answer to your queries!!


Telescope and it’s applications

Do you remember the time you’d sit on your bed pretending to steer an imaginary ship? Your younger siblings used to yell, “Aye, Captain!” while you did your best imitation of Popeye. You’d roll a newspaper and peer out of one end spotting a whale through your makeshift telescope. And then one fine day, you were thrilled (maybe not so thrilled!) to discover what exactly a telescope is? Well Watson, time for us to show to the young ones (siblings, kids or cousins) interesting things about the telescope!

What is a telescope?

It is an optical instrument designed to make distant objects appear larger. It contains an arrangement of lenses, or curved mirrors and lenses, by which rays of light are collected and focused. The resulting image gets magnified.

On the lighter note, it’s a tube with two lenses that makes you see objects that are faaaaar away (yep, that far, really!) and makes them look BIG (yep, that big too!). Without this tube, the objects would be just little dots in the sky or the sea. Since I know you’re already rolling your eyes at me, so I promise to be all so serious as I describe the telescope.



How a Telescope Works

When you hold a magnifying glass a few inches away from a notebook page, the words on the page appear magnified. When you look at a distant object through the same magnifying glass, you see an upside-down image of the object.

Astronomical telescope

An astronomical telescope makes use of two lenses, one of which works in each of these ways. The lens in the front of the telescope (the objective lens) produces an upside-down image of the object. The lens near the eye (the eye lens) magnifies that upside-down image. As a result, you see distant objects closer.


Astronomical telescope

Optical telescope

An optical telescope however, gathers and focuses light from the visible part of the electromagnetic spectrum, to create a magnified image.


Optical telescope

There are 3 primary types of optical telescope:

  • Refractors, which use lenses
  • Reflectors, which use mirrors
  • Catadioptric telescopes, which use a combination of both lenses and mirrors

These telescopes increase the apparent size of distant objects as well as their apparent brightness.


          The first optical telescope was basically constructed by the lens-grinder Dutchman, Hans Lippershey in 1608. Interestingly, Galileo Galilei is sometimes wrongly credited with its invention. He built the first astronomical telescope from a tube containing two lenses of different focal lengths aligned on a single axis in the following year.

Galileo's Telescope

Galileo’s Telescope

With this telescope, he made the first telescopic observations of the sky. He discovered lunar mountains, four of Jupiter’s moons and sunspots. We learnt that Saturn had rings and that the Milky Way was not a cloud but a collection of stars! It was a revolution in the scientific world!! The secrets of the heavens finally seen! Since then, telescopes have increased in size and improved in image quality. Computers are now used to take photographs of the observations made with the help of telescopes.

Now that we know what the lens / mirror tube is all about and who made it, why not also discover what it does?

Applications of telescopes

  • They are used by astronomers most importantly, to discover the cosmic world in great detail. The Hubble telescope was used to discover galaxies beyond our own.
  • Before GPS, radar and sonar, the humble telescope was used to spot land by navigators in a ship. It was also used by merchant ship sailors, explorers and pirates. (Arrrr!!).
  • Telescopes are basically also used by ornithologists (bird scientists) for spotting rare birds from far away.

I sometimes wonder how astonishing it must’ve been for astronomers – to peer through a telescope and glimpse the true beauty of the heavens! The explorers of the past have relied on this invention to help them sail through uncharted waters. The telescope truly changed the way we humans viewed the world!

Oh and before I sign off, do check out this cool kit at (link) to make your own telescope!

We love to assist our visitors, students, parents in their quest to learn science, you are welcome to leave your questions / comments. Chat with us, use contact us from here or on our facebook page ( In conclusion, drop us an email for any other queries and we would certainly reply with an answer to your queries!!