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Series

Maître Lucas - Mathématiques

108 episodes
Master Lucas and his pupil will accompany you through educational videos aimed mainly at children aged 5 to 11. This series is dedicated to teaching and learning mathematics.
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  • Episodes (15)
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E33 : Débuter les soustractions .

6 min 28 s
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This video is an introduction to subtraction. Children understand the meaning of subtraction (remove or compare) and the meaning of the - sign. A few exercises are used to familiarize themselves with the calculations. Techniques that children can use are also introduced: fingers, cubes (or other objects) and the number line. It is…
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E34 : Distinguer droite et gauche .

8 min 46 s
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Distinguishing between the right and left hand is a learning process that takes time, practice and cognitive maturation. Generally, children rely on their dominant hand (especially the writing hand) to distinguish the left hand from the right hand. I also suggest in the video to draw colored dots on each hand in order to distinguish…
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E35 : Divisions posées sans reste .

5 min 26 s
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This video is an introduction to posed division. It is about understanding the concepts of dividend, divisor and quotient. The students learn how to pose division with a one-digit divisor. Euclidean division with remainder will be the subject of another video.
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E36 : Effectuer des additions en appui sur 10 .

7 min 27 s
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The purpose of this video is to do addition up to 20 with the help of the 10. This means that when doing an addition like 8+4, we break down the 4 to make 8+2+2 in order to go after the 10. This technique will be very useful later on when using the other tens.
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E37 : Figures géométriques : Carré, rectangle, triangle, rond .

4 min 49 s
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In this video, students will learn to recognize geometric shapes (square, rectangle, triangle, round) based on their characteristics (number of sides). They recognize these shapes regardless of size or orientation. Conversely, the characteristics are given and the students must recognize the figure.
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E38 : La division .

4 min 42 s
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The purpose of this video is not to do actual division, but rather to introduce students to fair sharing. Master Lucas proposes different concrete sharing situations that the students should know and that they can reproduce. He also makes reference to groups that allow for a link with multiplication: with 6 I can make 2 groups of 3…
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E39 : La symétrie axiale .

5 min 49 s
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With this video students can take their first steps in symmetry. The idea is to understand what axial symmetry is by using folds. To begin, Master Lucas suggests folding a sheet of paper to obtain a line and painting on one side, then folding the paper again to obtain a symmetrical drawing. The fact of folding the sheet makes it…
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E40 : Le périmètre .

7 min 42 s
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In this video students can discover the concept of perimeter. They learn that the perimeter is the sum of the sides of a geometric figure. To facilitate the calculation of the perimeter of a square and a rectangle, there are two formulas: rectangle - P = (L+l) x 2 (be careful not to forget the parentheses because of the priorities of…
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E41 : Mathématique - Le sens des multiplications .

3 min 12 s
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This lesson is about multiplication. Master Lucas explains what multiplication is for and how it works.
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E42 : Les additions et soustractions en ligne jusqu'à 20 .

6 min 2 s
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The purpose of this video is to master several techniques for performing calculations to 20. Children understand the meaning of addition (add) and the meaning of subtraction (remove). They also recognize the symbol for addition (+) and subtraction (-). Several techniques are then used: counting on their fingers, moving forward or…
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E43 : Mathématique - Les additions posées sans retenues .

5 min 19 s
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In this video, students learn how to add numbers in rows and columns with no holds. The technique used is to add the units and then the tens. For the addition, it is specified that it is necessary to put the units under the units and the tens under the tens. Several exercises are proposed at the end to assimilate the concepts.
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E44 : Les contenances L, cL, mL .

9 min 51 s
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The objective is to know the units of measurement of capacity (hectoliter, decaliter, liter, deciliter, centiliter, milliliter) and to estimate measurements of capacity (e.g., to know that we do not use hL to measure the capacity of a coffee spoon). Next, I suggest using a table to convert measurements. At this point, we are only…
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E45 : Les doubles jusqu'à 10 .

3 min 57 s
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The objective of this video is to recognize a situation where there is a double. I chose to use dice to facilitate the visualization of the double and then to recognize them in calculations and finally simply with the words 'the double of...'. The proposed calculations make it possible to start memorizing, but it will not be…
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E46 : Les fractions .

8 min 4 s
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This video allows you to discover the notion of simple fraction. It is about discovering fractions from an everyday situation. The students have probably already talked about the notion of half and quarter and they discover how to represent them (numerator and denominator). They learn how to use fractions to divide.
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E47 : Les heures pleines .

4 min 48 s
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This video provides an opportunity to discuss reading full or battery hours with your children. I indicate that the large hand is used to show the hours and the small one the minutes. I suggest a color code to make it easier. I indicate that the minute hand should stay on 12 in order to make the battery hours. Then, the students just…
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    Levels:
    Elementary Kindergarten Grade 1 Grade 2 Grade 3 Grade 4 Grade 5 Grade 6 Grade 7 Grade 8 Secondary Grade 9 Grade 10
    Subjects:
    Mathematics Number Spatial Sense Programme de la maternelle et du jardin d’enfants Demonstrating Mathematics Behaviours
    Skills:
    Self-Directed Learning Communication Creativity Critical Thinking Problem Solving
    French level:
    A2: Waystage B1: Threshold
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