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Review Day 1 Topics 7.1-7.8

Unit 7 - Day 9

​Learning Objectives​
  • Review strategies for interpreting, estimating, and solving differential equations

Quick Lesson Plan
Activity: Crack the Code!



Lesson Handout


Crack the Code! is an engaging activity for individuals, pairs, or groups of students. A four-digit code is required to successfully complete the game. Students discover each digit by completing four activities designed to review the main concepts in Unit 7. 

Teaching Tips

Cut the worksheets in half so each problem is on its own sheet of paper. Have students work in their group to solve the first question. When they have finished, they should pick up the next problem. Handing out all the problems at once tends to discourage group work and lead students to a divide-and-conquer approach. Once students have solved all four questions, they should write their four-digit code on the board. As the teacher, you should only tell them if it is correct or incorrect (we don’t tell them how many of the digits are incorrect!). Once a group has posted a code, they cannot give another guess until at least two groups have written up a code. This is to reduce trial and error approaches. Students are engaged in this activity and minimal direction is needed. Our students had written more than 12 codes on the board before the correct code was found! Get ready to heart plenty of peer-to-peer discussion! At the end of the activity, review the four problems and answer any remaining questions. You could have groups take turns presenting the problems and their thought process if time permits.

The correct code is 4-8-3-5.
In question A, I and II are correct.
In question B, ALL but II are separable.
In question C, IV, VI, and VII are true.
In question D, I, III, V, VIII, and IX represent exponential growth.

Exam Insights

The problems found in Crack the Code! mirror questions typically found on the multiple-choice section of the AP Test. Unlike a testing situation, however, students are encouraged to share their thinking and critically evaluate the understanding of their peers.

Student Misconceptions

As you move around the room, listen for errors in understanding. Use student discussions to design review activities, guide whole-class discussions, or create a focused homework assignment.

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