Scratch and Grade 5 Triangles - TLLP Activity 3

This is the third in a series of blog posts connected to the Teacher Learning and Leadership (TLLP) I am part of. Our goal was to “Investigate ways that students can use Computational Thinking, across the Curriculum, to problem solve, create and remix - maximizing available technology.”

I need to thank Cliff Kraeker @kraekerc for the genesis of this idea. A colleague was using part of his Coding Quest Education Program and I made some variations to the lesson for my Grade 5 class.

Curriculum Connections - Grade 5 - Mathematics (Geometry)

By the end of Grade 5, students will:

• identify triangles (i.e., acute, right, obtuse, scalene, isosceles, equilateral), and classify them according to angle and side properties
• construct triangles, using a variety of tools (e.g., protractor, compass, dynamic geometry software), given acute or right angles and side measurements

Procedure (Over several periods, depending on knowledge and understanding)

1./ My students were familiar with the different triangles and most could already name them all. Experiences in earlier grades were obviously paying dividends. The review period for the terms (acute, right, obtuse, scalene, isosceles & equilateral) were quick. A brief review of an interior measure of an angle and an exterior measure of an angle is also helpful.

2./ We did a paper cutting activity where students were encouraged to make a large triangle of any kind on a standard sheet of paper. We cut the triangles out and then cut each corner off on a slight curve. We assembled the curves together and, in every case, we formed a rudimentary semicircle. The following guiding questions helped them come to some realizations

• How many degrees in a circle?  What about half a circle?
• If all of us could make a half circle from the corners or our unique triangles, what does the tell us about all triangles?
• If an equilateral triangle has three corners with interior angles that are the same, and they add up to 180 degrees...What will each corner measure?
• If a right triangle has a corner that measures 90 degrees - what do the other two angles measure? BONUS: Is a right triangle always an isosceles triangle?
• If an isosceles triangle has two angles that measure 80 degrees, what will the third be? How do you know?

3./ As a kinesthetic learning activity students put a strip of masking tape on an open floor space. One partner walks the tape and turns his/her body to begin to walk an equilateral triangle at the corner (vertex). Before continuing, they must answer the question.

How many degrees did I turn my body? Was it more than 60 degrees? Was it more than 90?

 

The realization that they actually turned 120 degrees is an important one for the coding they will eventually do in Scratch. The interior angle is 60, but the person, or pen or coded line actually turns the distance of the exterior angle. The activity can continue as students explore the space for isosceles, right, scalene, obtuse and acute triangles. In previous years. In previous years, I would encourage them to mark the sides with masking tape - but this did not serve to enhance their understanding and took up too much time...and tape.

Coding with Scratch

The students are shown the following example.

However, it is paused after the Equilateral Triangle is shown. Expectations are discussed.

• Using any sprite and the pen tool, create three different triangles.
• Using the “say” function - provide your viewer with information about the triangle.
• You must provide at least 3 truths about the triangle - but you can add more.
• Use any background and feel free to add sound effects.
• You can record your voice reading the information that you are “saying” on screen.
• You can work with a partner, but must do an equitable amount of the work.

Students exceeded expectations, as seen here and here

The part they liked the best - beyond the absence of boring worksheets.

• They got to choose which triangles they would share.
• There was flexibility on the information they chose to share.
• They liked the challenge of the scalene triangle.
• They liked the freedom to add music, moving images, colourful backgrounds.
• They loved working with a partner.

Differentiation

• Struggling students were allowed to use a large section of my code and remix it.
• Students with limited proficiency copied code from handouts, and were encouraged to look for patterns that could be duplicated.
• Students comfortable with the program created it on their own - referencing my code when necessary.
• Advanced students were encouraged to find a more interesting approach to the code and the final product or to find a different way to code it.

We shared our final products on Edmodo in order to allow other students to offer positive feedback.

Hints (Or Problem Solving Opportunities for them to debug)

• Show them the “Clear Graphic Effects” and “Clear” option that starts their program.
• Remind them that their Sprite needs to be reset with “Point in direction 90” - otherwise, they can’t test and debug as they are building their script.
• Suggest that they start their first triangle well away from a central location - this will allow them room for the other two.

Have Fun - I think you will enjoy seeing and evaluating the results.

A Report Card comment could read:

"Name was able to construct and identify a number of different triangles according to angle and side properties using dynamic geometric software with (insert modifier here)."