Estimation Skills Sorely Lacking
McAleer, posted May 8, 2017 —
I asked my students the same
question; this is a breakdown of their estimates:
1–2 ft.: 20 percent
2–3 ft.: 40 percent
3–4 ft.: 15 percent
4–5 ft.: 15 percent
5–6 ft.: 5 percent
6–7 ft.: 5 percent
Over 7 ft.: 0 students
Much to my students’
surprise, the actual answer is between 10–12 ft.
Estimation is a practiced yet
often undervalued skill in the mathematics classroom. Too frequently, we use
estimation as an isolated practice at the end or at the beginning of class and
generally spend only two to five minutes on it. An estimation activity is
viewed as something fun that gets students involved, but it is often not
discussed beyond “Yea, you were close!” Estimation can be much more. Presenting
an estimation activity should be an opportunity to refine and make our
estimating skills more precise.
We are constantly robbing our
students of opportunities to jump into mathematics using what every child has: intuition.
Some students have better estimation skills than others, but providing
opportunities for students to discuss how they approach estimation is important
and necessary in our classrooms. We must make time for these types of exercises,
and these opportunities should not be brief or an activity rated “correct or
incorrect.” Talking about possible approaches to a task and refining these
approaches is just as important if not more so.
Estimation activities cannot
be done in isolation within a math class. They should be part of the
conversation of mathematics and should lead to the discovery of efficient ways
to mathematize the world. They cannot and should not be relegated to five-minute
warm-ups or exit ticket exercises in which the reward is whether the student is
right or wrong. We need to find the time to do these tasks thoughtfully and
carefully in the classroom.
In my next post, I will be discussing best practices for how to implement
estimation into your classroom.
Jen McAleer is the head of middle school mathematics
(grades 6–8) at the Carroll School in Lincoln, Massachusetts. The Carroll
School serves students with language- based learning difficulties who also tend
to struggle with mathematics. McAleer has been teaching middle school for ten years
and has a passion to give all students a voice in mathematics and provide them
with opportunities to be and feel successful working with higher-level content,
despite their struggles with procedures and computation.