LEARNING EXPERIENCE
Estimation Strategies
ENGAGE (10 min.)
 Review expectations of working in the outdoor classroom.
 Ask students to record some quick weather observations in their
journal.
 Pull a large weed or point to a plant growing in the garden. Ask
students to estimate how many leaves they believe are growing
on that plant. What strategies can they use to come up with their
estimate? Is their estimate reasonable?
Grade
3rd - 5th
Timeframe
45 - 60 minutes
Materials
 Journals and pencils
 Tear by hand packaging
tape
EXPLORE (20 min.)
 Tell students that they need to move around the outdoor
classroom and choose at least 5 plants that they should use to
estimate the number of leaves.
 For each plant, the students should record:
o Name of the plant (if known)
o Quick sketch of the plant
o Estimate
o Strategies used for determining the estimate (i.e. I counted the leaves on one branch and
multiplied by the number of branches)
EXPLAIN (15 min.)
 Bring students back to central gathering area. Ask them to share some of their estimates. Have the
class determine whether an individual’s estimate is reasonable or not. Ask students to share some of
the strategies they used for their estimates.
 Ask students to choose just one of their plant leaf estimates, and divide students into pairs. In their
pairs, students should use the numbers they have for their estimates to find the:
o sum
o difference
o greater than/less than comparison
ELABORATE (10 min.)
 Mix up pairs and have them do the same math calculations using the number from a different partner.
 Encourage students to using rounding skills to the nearest 10 or 100 when solving their plant leaf
estimation problems.
 Gather group back together and lead a discussion of which group had the largest sum, smallest
difference, etc.
EVALUATE
 Students tape a leaf into their journals using tear by hand (tear-able) packaging tape from one of the
plants they used to estimate.
Copyright  2014 REAL School Gardens
www.realschoolgardens.org
OBJECTIVES
Math
3.4 B round to the nearest 10 or 100 or use compatible numbers to estimate solutions to addition and
subtraction problems;
4.3 A use addition and subtraction to solve problems involving whole numbers
4.5 A round whole numbers to the nearest ten, hundred, or thousand to approximate reasonable results in
problem situations
5.3 A estimate to determine solutions to mathematical and real-world problems involving addition,
subtraction, multiplication, or division
Copyright  2014 REAL School Gardens
www.realschoolgardens.org/lessons