In this optics activity, learners discover that when they rotate a special black and white pattern called a Benham's Disk, it produces the illusion of colored rings. Learners experiment with the speed of rotation and direction of rotation to observe varying patterns. Use this activity to explain to learners how our eyes detect color and how different color receptors in the eye respond at different rates.
In this activity, learners burn a peanut, which produces a flame that can be used to boil away water and count the calories contained in the peanut. Learners use a formula to calculate the calories in a peanut and then differentiate between food calories and physicist calories as well as calories and joules.
In this demonstration, cook a cake using the heat produced when the cake batter conducts an electric current. Because of safety concerns, this activity should be conducted as a demonstration only and learners should be kept at a safe distance.
In this electrochemistry activity, learners will explore two examples of electroplating. In Part 1, zinc from a galvanized nail (an iron nail which has been coated with zinc by dipping it in molten zinc) will be plated onto a copper penny. In Part 2, copper from a penny will be plated onto a nickel.
This is an activity about a very important ingredient in most baked goods - gluten! Why is gluten so important? Without it, there would be nothing to hold the gas that makes bread rise. Learners will experiment with different types of flour to get a feel for gluten, and discover why using different flours can lead to such different results in the kitchen.
In this activity, learners use a laser pointer and two small rotating mirrors to create a variety of fascinating patterns, which can be easily and dramatically projected on a wall or screen. In this version of the activity, learners use binder clips to build the base of the device. Educators can use a pre-assembled device for demonstration purposes or engage learners in the building process.
To understand how skaters turn in midair, try this little experiment! Individuals can do this activity alone, but it works better with a partner. Used in conjuncture with the rest of the Exploratorium's Skateboard Science website, this activity and others explore the physics of skateboard tricks.
In this activity, learners explore the question "What is paper?" Learners discover the processes and materials required to make paper while experimenting with different recycled fibers and tools.
In this activity, learners construct a device out of a piezoelectric igniter, like those used as barbecue lighters. Learners use the device to remotely start current flowing in a simple series circuit containing a small electric fan.
In this activity, learners work in groups to determine the mass and volume of four samples: glass marbles, steel washers or nuts, pieces of pine wood, and pieces of PVC pipe. Learners then plot the data points on a large class graph of mass vs. volume to discover that data points for a particular material form a straight line, the slope of which gives the density of the material.
In this activity, learners explore how different deodorants work. Learners treat agar plates with different types of deodorants and compare the bacteria growth on the plates to the control sample.
In this activity, learners build a simple mechanism that regulates the "escape" of energy released by a falling weight by portioning it into discrete amounts. Escapements are found in mechanical clocks, such as those driven by a pendulum or a spring. Learners will build the wrapping form of escapement said to be used in a fifteenth-century German clock.
In this activity, learners use their feet to estimate distances. Learners calculate the distance of one step in centimeters by measuring 10 steps at a time to reduce measurement error. Learners can use their stride ruler to measure the distance between different points on the playground as an extension activity.
In this activity, learners use a simple trick of perspective to dress friends in tiny cutout clothing. Learners make tiny pants out of card stock and tape them to the end of a stick. Then, learners hold them in front of a friend standing in the distance so that it looks like the friend is wearing the tiny pants. Learners can take photos and post them on the site's Flickr page. Use this optical illusion activity to discuss depth perception.