Students determine the mass and volume of soil samples and calculate the density of the soils. They use this information to determine the suitability of the soil to support a building foundation.

This lesson highlights the similarities between human sensors and their engineering counterparts. Taking this approach enables students to view the human body as a system, that is, from the perspective of an engineer. Humans have recreated most human sensors in robots – eyes, ears and sensors for temperature, touch and smell. The lesson inculdes a PowerPoint file that is programmed to run a Jeopardy-style game as a fun assessment tool.

Through six lesson/activity sets, students learn about the functioning of sensors, both human and robotic. In the activities, student groups use LEGO MINDSTORMS(TM) NXT robots and components to study human senses (sight, hearing, smell, taste, touch) in more detail than in previous units in the series. They also learn about the human made rotation, touch, sound, light and ultrasonic sensors. "Stimulus-sensor-coordinator-effector-response" pathways are used to describe the processes as well as similarities between human/animal and robotic equivalent sensory systems. The important concept of sensors converting/transducing signals is emphasized. Through assorted engineering design challenges, students program the LEGO robots to respond to input from various LEGO sensors. The overall framework reinforces the theme of the human body as a system with sensors that is, from an engineering perspective. PowerPoint® presentations, quizzes and worksheets are provided throughout the unit.

Students learn more about forces by examining the force of gravitational attraction. They observe how objects fall and measure the force of gravitational attraction upon objects.

Students learn how to program using loops and switches. They see how loops enable us to easily and efficiently tell a computer to keep repeating an operation. They also see that switches permit programs to follow different instructions based on whether or not preconditions are fulfilled. Using the LEGO MINDSTORMS(TM) NXT robots, sensors and software, student pairs perform three mini programming activities using loops and switches individually, and then combined. With practice, they incorporate these tools into their programming skill sets in preparation for the associated activity. A PowerPoint® presentation, pre/post quizzes and worksheet are provided.

Building on the programming basics learned so far in the unit, students next learn how to program using sensors rather than by specifying exact durations. They start with an examination of algorithms and move to an understanding of conditional commands (until, then), which require the use of wait blocks. Working with the LEGO MINDSTORMS(TM) NXT robots and software, they learn about wait blocks and how to use them in conjunction with move blocks set with unlimited duration. To help with comprehension and prepare them for the associated activity programming challenges, volunteer students act out a maze demo and student groups conclude by programming LEGO robots to navigate a simple maze using wait block programming. A PowerPoint® presentation, a worksheet and pre/post quizzes are provided.

During this lesson, students start to see the data structure they will use to store their images, towards finding a solution to this unit's Grand Challenge. Students are introduced to two-dimensional arrays and vector classes. Then they are guided to see that a vector class is the most efficient way of storing the data for their images. Grand Challenge: To write a program to simulate peripheral vision by merging two images.

Students learn more about how light sensors work, reinforcing their similarities to the human sense of sight. They look at the light sensing process incoming light converted to electrical signals sent to the brain through the human eye anatomy as well as human-made electrical light sensors. A mini-activity, which uses LEGO MINDSTORMS(TM) NXT intelligent bricks and light sensors gives students a chance to investigate how light sensors function in preparation for the associated activity involving the light sensors and taskbots. A PowerPoint® presentation explains stimulus-to-response pathways, sensor fundamentals, and details about the LEGO light sensor, including its two modes of gathering data and what its numerical value readings mean. Students take pre/post quizzes and watch a short online video. This lesson and its associated activity enable students to gain a deeper understanding of how robots can take sensor input and use it to make decisions via programming.

Students learn about how sound sensors work, reinforcing their similarities to the human sense of hearing. They look at the hearing process sound waves converted to electrical signals sent to the brain through human ear anatomy as well as sound sensors. A mini-activity, which uses LEGO MINDSTORMS(TM) NXT intelligent bricks and sound sensors gives students a chance to experiment with the sound sensors in preparation for the associated activity involving the sound sensors and taskbots. A PowerPoint® presentation explains stimulus-to-response pathways, sensor fundamentals, the unit of decibels, and details about the LEGO sound sensor, including how readings are displayed and its three modes of programming sound input. Students take pre/post quizzes and watch a short online video. This lesson and its associated activity enable students to appreciate how robots can take sensor input and use it to make decisions to via programming.

Students learn about how touch sensors work, while reinforcing their similarities to the human sense of touch. They look at human senses and their electronic imitators, with special focus on the nervous system, skin and touch sensors. A PowerPoint® presentation explains stimulus-to-response pathways, how touch sensors are made and work, and then gives students a chance to handle and get familiar with the LEGO touch sensor, including programming LEGO MINDSTORMS(TM) NXT robots to use touch sensor input to play music. Students take pre/post quizzes and watch a short online video. The mini-activities prepare students for the associated activity. This lesson and its associated activity enables students to appreciate how robots can take input from sensors, and use that to make decisions to move.

Students learn about how ultrasonic sensors work, reinforcing the connection between this sensor and how humans, bats and dolphins estimate distance. They learn the echolocation process sound waves transmitted, bounced back and received, with the time difference used to calculate the distance of objects. Two mini-activities, which use LEGO MINDSTORMS(TM) NXT robots and ultrasonic sensors, give students a chance to experiment with ultrasonic sensors in preparation for the associated activity. A PowerPoint® presentation explains stimulus-to-response pathways, sensor fundamentals, and details about the LEGO ultrasonic sensor. Pre/post quizzes are provided. This lesson and its associated activity enable students to gain a deeper understanding of how robots can take sensor input and use it to make decisions via programming.

Student teams design and conduct quality-control experiments to test the reliability of several ultraviolet protection factors. Students use UV-detecting beads in their experimental designs to test the effectiveness of various types of sunscreens and sunblock. For example, they might examine zinc oxide nanoparticles versus traditional organic sun protection factors. UV intensity is quantitatively measured by UVA and UVB Vernier sensors, and students record and graph their results. By designing and conducting this experiment, students compare various substances, while learning about quality control.

While learning about volcanoes, magma and lava flows, students learn about the properties of liquid movement, coming to understand viscosity and other factors that increase and decrease liquid flow. They also learn about lava composition and its risk to human settlements.

Students practice their multiplication skills using robots with wheels built from LEGO® MINDSTORMS® NXT kits. They brainstorm distance travelled by the robots without physically measuring distance and then apply their math skills to correctly calculate the distance and compare their guesses with physical measurements. Through this activity, students estimate parameters other than by physically measuring them, practice multiplication, develop measuring skills, and use their creativity to come up with successful solutions.

Students conduct experiments to determine what environmental factors favor decomposition by soil microbes. They use chunks of carrots for the materials to be decomposed, and their experiments are carried out in plastic bags filled with dirt. Every few days students remove the carrots from the dirt and weigh them. Depending on the experimental conditions, after a few weeks most of the carrots have decomposed completely.

Students measure the permeability of different types of soils, compare results and realize the importance of size, voids and density in permeability response.

Students learn about porosity and permeability and relate these concepts to groundwater flow. They use simple materials to conduct a porosity experiment and use the data to understand how environmental engineers decide on the placement and treatment of a drinking water well.

Students determine the coefficient of restitution (or the elasticity) for super balls. Working in pairs, they drop balls from a meter height and determine how high they bounce. They measure, record and repeat the process to gather data to calculate average bounce heights and coefficients of elasticity. Then they extrapolate to determine the height the ball would bounce if dropped from much higher heights.

Students learn about the nature of thermal energy, temperature and how materials store thermal energy. They discuss the difference between conduction, convection and radiation of thermal energy, and complete activities in which they investigate the difference between temperature, thermal energy and the heat capacity of different materials. Students also learn how some engineering requires an understanding of thermal energy.

In this lesson and its associated activity, students conduct a simple test to determine how many drops of each of three liquids can be placed on a penny before spilling over. The three liquids are water, rubbing alcohol, and vegetable oil; because of their different surface tensions, more water can be piled on top of a penny than either of the other two liquids. However, this is not the main point of the activity. Instead, students are asked to come up with an explanation for their observations about the different amounts of liquids a penny can hold. In other words, they are asked to make hypotheses that explain their observations, and because middle school students are not likely to have prior knowledge of the property of surface tension, their hypotheses are not likely to include this idea. Then they are asked to come up with ways to test their hypotheses, although they do not need to actually test their hypotheses. The important points for students to realize are that 1) the tests they devise must fit their hypotheses, and 2) the hypotheses they come up with must be testable in order to be useful.