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reSolve: Tree Biomass
In this sequence of two lessons, students investigate how many trees would be required to supply paper for their school for a year. Students use similar triangles, Pythagoras' Theorem and algebra to design and construct a Biltmore stick, used to measure the diameter and height of a tree. They measure trees, calculate their volume and use the density of the tree to find the dry mass of the tree. They estimate the amount of paper used in the school and hence estimate the number of trees that need to be cut down to supply the school's paper needs. The lessons are outlined in detail including curriculum links, vocabulary, sample answers, discussion points and student resources. This sequence is part of the reSolve: Mathematics by Inquiry program.
Additional details 

Year level(s)  Year 9 

Audience  Teacher 
Purpose  Teaching resource 
Format  Downloadable resources 
Teaching strategies and pedagogical approaches  Mathematics investigation 
Keywords  volume, cylinders, ratios, scale, similarity 
Curriculum alignment 

Curriculum connections  Numeracy 
Strand and focus  Measurement, Build understanding, Apply understanding 
Topics  Area, volume and surface area, Proportion, rates and ratios, Pythagoras and trigonometry 
AC: Mathematics content descriptions 
ACMMG217
Calculate the surface area and volume of cylinders and solve related problems
ACMMG221
Solve problems using ratio and scale factors in similar figures
ACMMG222
Investigate Pythagoras’ Theorem and its application to solving simple problems involving right angled triangles

National numeracy learning progression 
Comparing units (ratios, rates and proportion)
Understanding geometric properties  UGP6 
Copyright details 

Organisation  reSolve Maths by Inquiry 
Copyright  © Australian Government Department of Education, Skills and Employment 2021. Creative Commons BYNCSA 4.0. 
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