Measuring stem circumferences
Develop observation and data collection skills while exploring plant growth.
Learning objectives:
- Measure stem circumferences accurately in cm and mm
- Solve gardening-focused problems, converting between m, cm and mm
- Create problems based on conversion between m, cm and mm
Curriculum links:
- Maths: Measure and compare lengths in m, cm and mm
Jump to
Key vocabulary
Equipment
- Rulers showing cm and mm
- String
- Pencils
- Recording table
Introduction
Set a challenge to calculate amounts of string needed to stake stems across the garden to prevent wind damage.
Demonstrate stem circumference measurement by:
- Wrapping string around a stem and holding the place where the string meets
- Accurately measuring the amount of string used using a ruler
Main activity
Pupils work in pairs accurately measuring and recording the circumference of a variety of stems using string and a ruler.
- Pupils complete a recording table converting between m, cm and mm
- Pupils use their recording table to answer measurement problems and generate new problems
Plenary and assessment questions
Plenary
Invite pairs to share their new measurement problems.
Assessment questions
- Was it easier to record the stem circumferences in m, cm or mm?
- What advice would you give someone who wanted to measure the circumference of a large tree trunk accurately?
Additional information
This activity provides an opportunity to learn outside with plants as a route to developing maths understanding and provides a real-life context for learning.
The activity offers an opportunity for pupils to have hands-on experience selecting which plant stems they would like to measure and to consolidate their understanding by measuring the circumference of a variety of stems, before solving and generating measurement problems.