Controller down. Counting mode on.
Mission:
Island Stats!
At the fishing festival everything is counted, sorted and stacked. Lots of little marks turn into a graph everyone understands.
draw!
How to practice: one mission a day (15 to 20 minutes) and 5 minutes in the trainer. For the graphs you need a pencil and a ruler.
Tablet tip: In the graph trainer you read tally marks, bars and picture graphs, with a hint for every mistake and a 10-problem test.
Open the trainerCounting · tally marks
Mark by Mark
At the fishing festival every catch is counted. With tally marks it is quick and you don’t lose count.
How many marks?
Six tallies.
Draw the tally marks
| Number | Tally marks |
|---|---|
| 6 | |
| 11 | |
| 17 |
On screen: add marks with + and −.
Raw data · frequency table
The Big Catch
At the fishing festival Pixel wrote down every catch, one letter per fish. An unsorted list like this is called raw data.
Tally chart and frequency table
Make one mark in the right row for each fish. Then count the marks and write the number. The number is also called the frequency.
| Fish | Tally marks | Number |
|---|---|---|
| HHerring | ||
| MMackerel | ||
| SSalmon | ||
| CCrab | ||
| TTuna | ||
| Total |
Tip: cross out the letters in the list as you count.
Questions about the table
Three questions.
Drawing bar graphs
Build the Bars
A table is exact, but a graph shows at a glance what is biggest. Now you build the bars.
The big catch as a bar graph
1 square = 1 fish.
Tap in each column until the bar has the right height. On the printout you also label the axes and give the graph a title.
- Write the numbers 0 to 12 on the vertical axis.
- Write the kinds of fish under the bars, in the order of the table.
- Draw the bars.
- Give the graph a title:
Five bars.
Choose the scale yourself
The grid is only 9 squares tall and the largest value is 80. Which scale fits? 1 square = 1 / 5 / 10 visitors.Then number the vertical axis, label the horizontal axis with the stands in the order of the table, and draw the bars. Then tap each bar to the right height. The axis numbers appear as soon as your scale is right.
| Stand | Visitors |
|---|---|
| Ice cream | 60 |
| Pizza | 45 |
| Ferris wheel | 80 |
| Fishing | 35 |
| Stage | 70 |
For 45 and 35, the bars end halfway up a square (at the dashed lines).
Five bars.
Reading graphs
Graph Detective
A detective looks closely: what is written on the axis? How much is one square worth?
Bar graph with a scale
Six answers.
Horizontal bar graph: favorite island activity
Three questions.
Picture graph: one fish picture stands for 10 fish
Three days.
Everything mixed · like a test
Test Check
Counting, table, graph: everything once, short and sweet. Then you know what you’ve got.
Raw data: 18 kids name their favorite flavor
Four flavors.
Error detective: one bar is drawn wrong
| Flavor | Scoops |
|---|---|
| Vanilla | 9 |
| Chocolate | 12 |
| Strawberry | 7 |
| Lemon | 4 |
Two answers.
Traffic light: how sure are you?
Extra · on a tablet or computer
Graph Trainer
Read the value and tap the number. Always check how much one square or one picture is worth.
Test: 10 problems
10 problems with a timer. Wrong ones go on your practice list.
Your last tests:
The check buttons count correct boxes. Compare explanations and answer sentences with the answer key yourself.
ANSWER KEY · Try first, then compare.
Answers
1 · Mark by Mark
B 6 = | 11 = | 17 =
Typical mistake: not drawing the 5th mark across. Then you have to count every mark one by one.
2 · The Big Catch
Total: 36
B 1: Herring | 2: 11 − 4 = 7 | 3: Salmon + Tuna (7 + 4 = 11)
3 · Build the Bars
H: 11 squares | M: 8 squares | S: 7 squares | C: 6 squares | T: 4 squares
B Scale: 1 square = 10, vertical axis 0, 10, 20, …, 90; below: Ice cream, Pizza, Ferris wheel, Fishing, Stage
Ice cream: 6 | Pizza: 4.5 | Ferris wheel: 8 | Fishing: 3.5 | Stage: 7 squares
Typical mistake: drawing 45 squares for 45 visitors when 1 square = 10, or 4 instead of 4.5.
4 · Graph Detective
B 1: Fighting fires | 2: 9 | 3: 11 − 6 = 5
C Monday 35 | Tuesday 20 | Wednesday 45
Typical mistake: counting squares instead of using the scale. First check: how much is one square worth?
5 · Test Check
B Wrong: Strawberry. Correct: 3.5 squares (7 ÷ 2)
For grown-ups: what helps most
- When counting the raw data, have the child check off every entry. The total is the check.
- Before every graph ask: where does the axis start, and how much is one square worth?
- Use a pencil and ruler for drawing; bars the same width with gaps.