Learning Objectives (5-7 minutes)

1). Understand the concept of resistance and Ohm’s Law: The students will understand the concept of electrical resistance, how it’s measured, and the impact it has on current flow. They will also be able to understand and utilize Ohm’s Law in various scenarios. 2). Develop calculation skills for series and parallel resistor combinations. The students should be able to determine a circuit’s total resistance when the resistors are arranged either in series or parallel. Then they should be able to determine the current flowing through each resistor and the potential difference (voltage) across each one as well. 3) Use the knowledge gained to solve real-world problems. The students use their understanding of resistor combinations and Ohm’s law to solve practical electrical circuit problems. They will be able to correctly identify the resistor combinations in a circuit, and calculate appropriate voltage, current, and/or resistance values.

Secondary Objectives:

• Foster teamwork and communication: Collaborative activities give opportunities to work together and encourage effective communication while brainstorming and problem-solving.
• Encourage critical thinking and problem solving: Students are prompted through complex problems to reason critically, analyze data, develop a plan to solve the problem at hand, and assess the results.

Introduction (10-15 minutes)

1. Review of previous content: The teacher will start by reviewing previous electricity concepts like electrical current, voltage and electrical resistance. This can either be done through briefly going over the theory, or by having the students complete a short diagnostic to assess their understanding. It will ensure all learners have the foundation necessary for understanding the new content. 2). Problem situations: Two problem situations will serve as an engaging introduction to the lesson content. The first problem could be a scenario involving the need to calculate the equivalent resistance when the resistors are arranged in a series, while the second could also involve calculating equivalent resistance, but when the arrangement of resistors is parallel. Both situations will be designed to make the students curious about solving them. 3). Contextualization: The teacher should highlight the importance and relevance of this lesson by discussing the importance and applications of resistor combinations, giving everyday scenarios (like lightbulbs, showers and electronic devices) and examples of where they are used in the real-world. Real world examples could also include engineering fields like electrical engineering and telecommunications. 4). Topic introduction: To make students interested, the teacher can include a fun fact or story related to the lesson. An option is to share the history of Georg Simon Ohm, the physicist that this lesson’s law was named after, and how Ohm’s law helped advance an important concept about electricity. Another option is mentioning the significance of how electrical resistance plays a key role to the functioning of a fuse, a vital component for our electronic safety, which protects electrical devices from damage due to excess electrical current. Furthermore, visuals of circuits and electronic components could be shown, challenging students to identify resistor configurations.

Development (20-25 minutes)

1). Lab activity: "Series & Parallel Resistors" (10 - 12 min)

• Preparation: Prior to this lesson, the teacher should prepare the necessary materials for this activity. This includes but is not limited to: power supply (such as batteries), resistors of varying values, connecting wires, and a multimeter for measuring current and voltage.

• Grouping: Break the students into working groups no larger than 5. Each group will receive their own materials.

• Activity Description: Inform students that, for this activity, each team will create multiple basic electrical circuits, and then measure and calculate their total resistances, current flow through each resistor, as well as the potential difference (voltage). They will compare these experimental values to theoretical values.

• Activity Execution:** Each group is to create one series and one parallel circuit using the resistors provided. For both circuits, have students determine the total equivalent resistance, current flowing, and voltage present across each resistor and then record both experimental and theoretical calculations.

• Analysis of results: Once all measurements have been taken, and calculations have been completed, students will compare the results that they got from the experiment to the theoretical calculations. They will engage in a discussion about possible error sources and how they might get more precise results.

• Group discussion and reflection: Students come back together to have a class discussion, sharing their results and any difficulties encountered. The teacher is there as a facilitator, guiding them to make connections between the theory, real world application, and overall reinforcing understanding of the lesson's key concepts.

2). Fun activity - “Resistor Challenge” (10-12 min)

• Preparation: The “Resistor Challenge” game should be created before this lesson by the instructor. The game consists of a board game with spaces representing different resistors and mathematical operations. In addition to the board, cards containing different resistor values will be needed as well.

• Grouping:** Keep the students in their original groups from the last activity.

• Activity description: Students are informed about the goal, reaching the last square of the board game. To do so they must solve the resistor combinations that the board presents. For this, students will select a resistor value card and choose whether to place it either in series or in parallel with the resistor on the space they are on.

• Activity Execution:** The students take turns playing, brainstorming together about which strategy is best to complete the challenge. The instructor should monitor the progress and clarify doubts that may arise.

• Group discussion & reflection: After having completed the game, students and teacher have a group reflection. The teacher encourages a conversation about strategies used, difficulties faced, and solutions gefunden. From there the teacher guides the conversation towards the connection between the game, and series-parallel resistor combinations and Ohm's Law.

Closure (8 - 10 min)

1). Group Discussion (3- 4 min)

• Have the class come back together for the last time and begin group discussion about specific solutions and/or conclusions that each team encountered while completing the activities.

• Students are encouraged to discuss observations and strategies, sharing any difficulties they experienced.

• Teacher facilitates conversation, interjecting questions which prompt students to connect theory to practice and reflect on essential concepts.

2. Connecting to the Theory (2 - 3 min)

• Teacher creates connection to the theory presented at the beginning of class.

• Teacher helps students understand how the learned concepts (electrical resistance and Ohm’s Law) were used in the activities to solve electrical circuit problems.

• The problem situations given in the Introduction can be revisited and discussed, showing students how the activities prepared them to solve those original questions.

3. Final Reflection (2 -3 min)

• Have learners take a moment to think about what they learned.

• Teacher asks closing questions such as: “Which concept was most significant to you today?” “Were there any questions left unanswered?”.

• Students are given a moment to silently think, then the instructor calls on volunteers who wish to contribute.

• This step provides the opportunity for students to solidify their understanding while helping the instructor assess the overall effectiveness of the activities in promoting understanding and find any misconceptions that need to be addressed.

Conclusion ( 5 - 7 min)

1). Review of Concepts (1-2 min)

• Instructor reviews and summarizes the main concepts discussed throughout the lesson. To include definitions of resistance, Ohm’s Law, and series and parallel resistor combination types.

• Emphasize the interconnectedness of the concepts and how critical they are toward understanding electrical circuits.

2). Theory-Practice-Applications Connections* (1- 2 min)

• Instructor highlights how the lesson blended theory, practice and applications. Discuss the introduction to theory, opportunities to practice during activities, and how discussions connected to applications in the real world all contribute to student learning.

• Instructor reinforces that good theory understanding is imperative to solving practical problems and applying this understanding to real world situations.

3. Supplemental Materials(1-2min)

• Instructor provides suggestions for supplemental resources for those who wish to further explore the material.

  • Ex. Mention how the website Khan Academy has a series of videos and interactive practice problems on electricity and circuits, or the PhET Interactive Simulations app allows users to virtually experiment with physics principles, including resistor combinations.

4. Relevance of Concepts in Everyday life ( 1 min)

• In closing remarks the instructor connects how these topics play an important role in students’ lives.

• Mention how understanding resistor combinations can help with home repairs on appliances, or other electrical DIY tasks.

• Discuss future career/education applications in fields like electrical engineering, electronics, automation, etc.