# Video/Exponentials

These videos were filmed at Masiphumelele Primary School, Khayelitsha, W. Cape, South Africa, in March 2012. They are from a lesson on the powers of two.

# 1 About Masiphumelele Primary School

In 2012, the situation of the school was as follows: The school is what's called "Quintile 3". The funding of schools depends on the level of the schools’ quintile. A school in quintile 1 is said to be the poorest of schools, taking into account the socio-economic status of the community around that school (poverty, unemployment, dependency on social grants, etc.), as determining factors for classifying a school. Many families come from rural areas in the Eastern Cape. All the same issues that were described for Luzuko Primary School also apply.

The school was built in the mid 1990s and has a large school hall and two functional computer rooms. The number of learners (across grades 1 to 7) is 1237. Grade R has 63 learners. The learners go on to about 14 different High Schools, some of which specialize in commerce or in mathematics and science. The performance levels are better than other schools but still not good. This is a popular primary school and oversubscribed.

For the learners and most teachers Xhosa is their first language and English their second language. Lessons are in Xhosa up to grade 3 with English taught as an additional language. From Grade 4 to Grade 7 all lessons are supposed to be taught in English with differing amounts of code switching. The Principal has said that she thought that the use of Xhosa was often not helpful, for example for the same shapes there are several different Xhosa words in different regions and no common agreement about which one to use. Public tests are all in English.

# 2 About the lessons

The lesson introduces the idea of exponentials, and in particular powers of 2. To get a sense of how quickly the exponential function rises, learners go to the school hall and use long rolls of paper to draw the function.

In the second lesson, the learners think about how to represent 2^x on a single sheet of paper.

# 3 Watch all videos

Use the "playlist" button in the top right or the "|<" and ">|" to skip through the playlist.

# 4 Video list

Wiki page | Title | Description | Duration | Series | Episode | Project |
---|---|---|---|---|---|---|

Video/Pindi exponentials 2.1-1.m4v | Introducing a problem with a story | Pindi introduces the problem ("The powers of two"). She begins the lesson by telling a story. She asks the students which option they would choose: A fixed amount of money, or a smaller amount which doubles every week. Learners give their opinion. | 2:35 | Video/Exponentials | 01 | OER4Schools |

Video/Pindi Exponentials2.1-2.mp4 | Learners doubling numbers | Two learners are working together to repeatedly double numbers and work out how much gold the man should receive. | 01:01 | Video/Exponentials | 02 | OER4Schools |

Video/Pindi Exponentials2.1-3.mp4 | Learners check answers | Pindi looks at the work of a pair of learners and questions whether they think a particular answer is correct. They are offered a calculator to check answers but prefer to work out for themselves. | 00:36 | Video/Exponentials | 03 | OER4Schools |

Video/Pindi Exponentials2.1-5.mp4 | Involving class in answering a question | A learner has noticed that the beginning of next week is called 'week 1' and asks what the current week could be called. The teacher asks the rest of the class, and another question quickly follows. | 01:05 | Video/Exponentials | 04 | OER4Schools |

Video/Pindi Exponentials2.1-7.mp4 | Giving answers and class making corrections | Pindi stops the class to give answers to the class. She encourages the learners to recite answers together and make corrections. | 01:29 | Video/Exponentials | 05 | OER4Schools |

Video/Pindi Exponentials2.2-9.mp4 | Class questioning and confusion | Pindi asks the class what they think the answer to two exponents multiplied together might be. She asks for the answer in exponent form which confuses a couple of learners. | 01:19 | Video/Exponentials | 06 | OER4Schools |

Video/Pindi Exponentials2.2-10.mp4 | Giving an example | Pindi follows up on the previous question and looks at why the rules of exponents work with the example on the board. | 01:20 | Video/Exponentials | 07 | OER4Schools |

Video/Pindi Exponentials2.2-11.mp4 | Pair work and explanations | Learners are instructed to work in pairs to answer questions with an added explanation of the method they used and why it works. | 01:28 | Video/Exponentials | 08 | OER4Schools |

Video/Pindi Exponentials2.3-14.mp4 | Table of values | Pindi helps the class to fill in their table of values which will be used to plot a graph of y=2^x. | 00:42 | Video/Exponentials | 09 | OER4Schools |

Video/Pindi Exponentials2.3-17.mp4 | Learners use measuring cards | Pindi shows what the graph should look like as learners use their measuring card to mark out points on the graph | 00:37 | Video/Exponentials | 10 | OER4Schools |

Video/Pindi Exponentials2.3-19.mp4 | Learners divide into groups | Learners enter the hall and divide into their groups to finish plotting their graphs. | 01:25 | Video/Exponentials | 11 | OER4Schools |

Video/Pindi Exponentials2.4-21.mp4 | Examing completed graphs | Pindi gathers the students back together to examine all of the completed graphs. | 00:31 | Video/Exponentials | 12 | OER4Schools |

Video/Pindi Exponentials2.4-22.mp4 | Checking and demonstrating plotting points | Pindi and the class look at all the graphs next to each other and check for mistakes. Pindi demonstrates how to plot the points. | 01:59 | Video/Exponentials | 13 | OER4Schools |

Video/Pindi Exponentials2.4-23.mp4 | Pindi checks one group's work | Pindi checks one group's work and helps them to make corrections. | 01:10 | Video/Exponentials | 14 | OER4Schools |

Video/Pindi Exponentials2.4-24.mp4 | Pupils return with graphs | The pupils are instructed to return with their graphs to the classroom. | 01:13 | Video/Exponentials | 15 | OER4Schools |

Video/Pindi Exponentials2.4-26.mp4 | Pupil make predictions | Pupils put their graphs up on the wall and mark in bold pen increasing values of 2^x. The graphs quickly get much taller and pupils are asked to predict where the next marks would be. | 02:51 | Video/Exponentials | 16 | OER4Schools |

Video/Pindi exponentials 2.3-18.m4v | Classroom management | Classroom management. Pindi asks the learners to go to the school hall to continue the investigation. | 1:56 | Video/Exponentials | 18 | OER4Schools |

Video/Pindi exponentials 2.4-21.m4v | Whole group work | Pindi asking the groups to come together with their work, so that the work can be compared and discussed. | 0:33 | Video/Exponentials | 21 | OER4Schools |

Video/Pindi exponentials 2.4-23.m4v | Graph group work | Group work activity on drawing the graph. Pindi shows the use of the "ruler" to a group. | 1:04 | Video/Exponentials | 23 | OER4Schools |