The topic of this video module is genetic basis for variation among humans. The main learning objective is that students will learn the genetic mechanisms that cause variation among humans (parents and children, brothers and sisters) and how to calculate the probability that two individuals will have an identical genetic makeup. This module does not require many prerequisites, only a general knowledge of DNA as the genetic material, as well as a knowledge of meiosis.
This video lesson highlights how science can be learned from daily life experiences. It emphasizes the ways in which simple laws of physics can be understood from personal observations and experiences, and in fact it demonstrates that we use these laws as if they were built into our instincts. The video also introduces Newton's laws of motion. The title, Gravity at Work, comes from a fascinating example of two laborers working at a construction site in Pakistan. In this lesson, Newtonian equations of motion are used to determine the velocities and height achieved by the projectile in a very simple and basic manner.
The unit “mole” is used in chemistry as a counting unit for measuring the amount of something. One mole of something has 6.02×1023 units of that thing. The magnitude of the number 6.02×1023 is challenging to imagine. The goal of this lesson is for students to understand just how many particles Avogadro's Number truly represents, or, how big is a mole. This lesson is meant for students currently enrolled in a first or second year chemistry course. This lesson is designed to be completed within one approximately 1 hour class; however, completion of optional activities 4 and 5 may require a longer class period or part of a second class period. This lesson requires only pencil and paper, as the activities suggested in this video place an emphasis on helping students develop their “back of the envelope” estimation skills. In fact, calculators and other measuring devices are explicitly discouraged. However, students may require additional supplies (poster board, colored pencils, markers, crayons, etc.) for the final optional/assessment activity, which involves creating a poster to demonstrate the size of a mole of their favorite macroscopic object.
This video is the second lesson in the How Cold Is Cold? BLOSSOMS series and examines the properties of materials under low temperature conditions. The video consists of a series of fascinating demonstrations with liquid nitrogen, which boils at 77K (-196 C -321 F). These demonstrations include the following: What goes up, may not come down; Is that supposed to be cold? - thermal insulation; Some properties of liquid nitrogen; Making ice cream - the slow way and the fast way; Try not to explode: expansion of liquid nitrogen and the ideal gas law; Making the air cold: phase changes and the affect on volume; No frozen fingers: the changes in mechanical properties; Resistivity at 77K; The magic magnet: the Meissner Effect; Cautions in using liquid nitrogen
This video lesson is part of a two-part series and introduces the concept of temperature. Temperature can be a challenging concept to convey since our perception is tied to words that are relative to our own experience, which varies quite a lot. A short activity to be performed in the classroom shows the need for a temperature scale since qualitative descriptions are not adequate. Temperatures that vary from the hottest to coldest recorded temperatures on earth are shown in advance of introducing the boiling temperatures of a number of cryogenic liquids.
The aim of this lesson is to introduce the concepts of heat and temperature, which many students find confusing. During the lesson, students will be asked to explore and discuss situations where even though the same amount of heat is absorbed by several substances, the increase in temperature of the substances is different. This video lesson presents a series of stories relating to heat and temperature, beginning with a visit to a factory where gamat oil is produced. In the video, a man dips his finger into boiling gamat oil yet feels no pain. The scene will draw students’ attention and raise their curiosity about how this is possible. Students will also carry out several experiments to compare and relate the situations where the same amount of heat absorbed by substances will result in different temperatures. By the end of this lesson, students will understand the term “specific heat capacity” and will recognize the difference between a high or low specific heat capacity. They will also understand the term “thermal diffusivity” and how this relates to the topic of the lesson. This lesson offers some authentic learning experiences where students will have the opportunity to relate the concept of heat and temperature to everyday situations. It will take about 50 minutes to complete - however, you may want to divide the lesson into two classes if the activities require more time.
In this lesson, we learn how insects can fly in the rain. The objective is to calculate the impact forces of raindrops on flying mosquitoes. Students will gain experience with using Newton's laws, gathering data from videos and graphs, and most importantly, the utility of making approximations. No calculus will be used in this lesson, but familiarity with torque and force balances is suggested. No calculators will be needed, but students should have pencil and paper to make estimations and, if possible, copies of the graphs provided with the lesson. Between lessons, students are recommended to discuss the assignments with their neighbors.
This lesson is about the estimation of the value of Pi. Based on previous knowledge, the students try to estimate Pi value using different methods, such as: direct physical measurements; a geometric probability model; and computer technology. This lesson is designed to stimulate the learning interests of students, to enrich their experience of solving practical problems, and to develop their critical thinking ability. To understand this lesson, students should have some mathematic knowledge about circles, coordinate systems, and geometric probability. They may also need to know something about Excel. To estimate Pi value by direct physical measurements, the students can use any round or cylindrical shaped objects around them, such as round cups or water bottles. When estimating Pi value by a geometric probability model, a dartboard and darts should be prepared before the class. You can also use other games to substitute the dart throwing game. For example, you can throw marbles to the target drawn on the floor. This lesson is about 45-50 minutes. If the students know little about Excel, the teacher may need one more lesson to explain and demonstrate how to use the computer to estimate Pi value. Downloadable from the website is a video demonstration about how to use Excel for estimating Pi.
The aim of this video lesson is to teach students about the different topologies of computer networks and how they function. The approach that is used is highly correlated with common knowledge about weddings and the local Malay culture associated with weddings. Students should be able to relate the act of delivering food to a large crowd of people to the basic principles of network topologies and the method of data transfer within each type of topology. The lesson will begin in a classroom with students working in small groups, answering assigned questions. Teaching aids such as color cards will be used. One student from each group will be appointed as the wedding event manager, and she/he will have to discuss and act out with group members in order to answer more challenging questions. At the end of the lesson, students will be asked to come up with their own version of a hybrid computer network topology. The lesson concept taught here not only educates students on computer topologies, but also introduces students to an important cultural perspective of Malaysia. Above all, this video is designed to assist students with their study of Computer Literacy in schools. The lesson will take up to 60 minutes to complete. Materials needed include: 10 red cards representing waitresses; 10 green cards representing waiters; 10 blue cards representing tables in the hall; a sketch book; and classroom tables and chairs.
This lesson uses the fundamentals of protein synthesis as a context for investigating the closest living relative to Tyrannosaurus rex and evaluating whether or not paleontologist and dinosaur expert, Jack Horner, will be able to "create" live dinosaurs in the lab. The first objective is for students to be able to access and properly utilize the NIH's protein sequence database to perform a BLAST, using biochemical evidence to determine T rex's closest living relative. The second objective is for students to be able to explain and evaluate Jack Horner's plans for creating live dinosaurs in the lab. The main prerequisite for the lesson is a basic understanding of protein synthesis, or the flow of information in the cell from DNA to RNA during transcription and then from RNA to protein during translation
This lesson presents the basics of aerodynamics by using kite flying as an example, i.e., forces acting on a flying object. Students will measure the net force acting on a kite due to blowing air and will learn how a simple instrument like a spring can be used to measure such force. They will also examine and experience how the force on the kite is transferred to the string in the form of tension and will again measure that tension with a simple spring. This lesson will take about 30 minutes to complete. One will need a calibrated spring to measure forces, as well as a few springs to study the coplanar forces.
The goal of this video lesson is to teach students about new and exciting ways of holding an election that they may not be aware of. Students will learn three different methods of voting: plurality, instant runoff, and the Borda count. They will be led through a voting experiment in which they will see the weakness of plurality when there are three or more candidates. This lesson will show that not every voting system is perfect, and that each has its strengths and weaknesses. It will also promote thought, discussion, and understanding of the various methods of voting.
The main aim of this lesson is to show students that distances may be determined without a meter stick—a concept fundamental to such measurements in astronomy. It introduces students to the main concepts behind the first rung of what astronomers call the distance ladder. The four main learning objectives are the following: 1) Explore, in practice, a means of measuring distances without what we most often consider the “direct” means: a meter stick; 2) Understand the limits of a method through the exploration of uncertainties; 3) Understand in the particular method used, the relationship between baseline and the accuracy of the measurement; and 4) Understand the astronomical applications and implications of the method and its limits. Students should be able to use trigonometry and know the relation between trigonometric functions and the triangle. A knowledge of derivatives is also needed to obtain the expression for the uncertainty on the distance measured. Students will need cardboard cut into disks. The number of disks is essentially equal to half the students in the class. Two straight drink straws and one pin per disk. Students will also need a protractor. The lesson should not take more than 50 minutes to complete if the students have the mathematical ability mentioned above. This lesson is complimentary to the BLOSSOMS lesson, "The Parallax Activity." The two lessons could be used sequentially - this one being more advanced - or they could be used separately.
In this lesson students will see the different types of evidence scientists use to understand evolutionary relationships among organisms. They will first practice by using shared physical characteristics to predict relationships among members of the cat family and then use this approach to predict primate relationships. They will compare their predictions to evidence provided by analyzing amino acid sequences and build a phylogenetic tree based on these sequences. Finally, they will look at the tree in the context of time in order to see divergence times.
This Protein Purification video lesson is intended to give students some insight into the process and tools that scientists and engineers use to explore proteins. It is designed to extend the knowledge of students who are already somewhat sophisticated and who have a good understanding of basic biology. The question that motivates this lesson is, ''what makes two cell types different?'' and this question is posed in several ways. Such scientific reasoning raises the experimental question: how could you study just a subset of specialized proteins that distinguish one cell type from another? Two techniques useful in this regard are considered in the lesson.
This lesson teaches students how to make decisions in the face of uncertainty by using decision trees. It is aimed for high school kids with a minimal background in probability; the students only need to know how to calculate the probability of two uncorrelated events both occurring (ie flipping 2 heads in a row). Over the course of this lesson, students will learn about the role of uncertainty in decision making, how to make and use a decision tree, how to use limiting cases to develop an intuition, and how this applies to everyday life. The video portion is about fifteen minutes, and the whole lesson, including activities, should be completed in about forty-five minutes. Some of the activities call for students to work in pairs, but a larger group is also okay, especially for the discussion centered activities. The required materials for this lesson are envelopes, small prizes, and some things similar in size and shape to the prize.
This lesson will explore the connections between magnetism in natural materials and electromagnetism. The ultimate goal will be for students to form an understanding that the source of magnetism in natural materials is moving charges. It is helpful, but not required, for the students to have some work with electricity, and other distance forces (such as gravity or the electric force). The lesson will probably take two 50-minute periods to complete. Although the video footage is brief, the activities are in depth, inquiry-based, and can take time for the students to explore. The materials are not specifically prescribed, but can include things such as bar magnets, compasses, iron filings, wire, batteries, steel bolts, coils, straws, and hot glue. The activities include drawing the magnetic fields of bar magnets and electromagnets. The activities also include making a magnet from a drinking straw and iron filings.
In this video lesson, the concept of momentum applied to hard-body collisions is explained using a number of simple demonstrations, all of which can be repeated in the classroom. Understanding Newton's Laws is fundamental to all of physics, and this lesson introduces the vital concepts of momentum and energy, and their conservation. Only some preliminary ideas of algebra are used here, and all the concepts presented can be found in any high-school level physics book. In terms of materials required, getting hold of large steel balls may not be easy, but large ball bearings can be procured easily. On the basis of what students have learned in the video, teachers can easily generate a large number of questions that relate to one's daily experiences, or which pose new challenges: for example, in a collision between a heavy and light vehicle, why do those inside the lighter one suffer less injury?
In this video lesson, students will learn about linear programming (LP) and will solve an LP problem using the graphical method. Its focus is on the famous "Stigler's diet" problem posed by the 1982 Nobel Laureate in economics, George Stigler. Based on his problem, students will formulate their own diet problem and solve it using the graphical method. The prerequisites to this lesson are basic algebra and geometry. The materials needed for the in-class activities include graphing paper and pencil. This lesson can be completed in one class of approximately one hour. If the teacher would like to cover the simplex algorithm by George Dantzig as an alternative solution method, an additional whole class period is suggested.
This learning video explores the mysterious physics behind boomerangs and other rapidly spinning objects. Students will get to make and throw their own boomerangs between video segments! A key idea presented is how torque causes the precession of angular momentum. One class period is required to complete this learning video, and the optimal prerequisites are a familiarity with forces, Newton's laws, vectors and time derivatives. Each student would need the following materials for boomerang construction: cardboard (roughly the size of a postcard), ruler, pencil/pen, scissors, protractor, and a stapler.