From data cards to clear procedures
Learn variables, iteration, filtering, flowcharts and data types through small examples you can trace by hand. No previous programming experience is needed.
Study sections
Follow the order or choose a sectionStart here: think in clear, repeatable steps
Computational thinking means turning a problem into clear steps that another person or a computer can follow. This course begins before…
02Meet the datasets: marks, bills and words
A dataset is a collection of related items. In this course, each item is drawn as a card. Each card has named fields. Different cards f…
03Variables and iteration: remember your progress
A variable is a named place to keep a value while a procedure runs. Iteration means repeating a set of steps over the items. Together,…
04Sums and averages: two variables, one scan
Counting adds 1 for each record. Summing adds a value from that record. You can do both in one scan, then divide to get an average.
05Filtering: count only the cards you want
A filter is a condition that selects the records relevant to a question. A filtered iteration still visits the records systematically,…
06Combine filters and keep separate group summaries
Some questions require more than one condition. For example, a record must have group F AND city Chennai. Check both fields, then updat…
07Flowcharts: draw decisions and repetition
A flowchart draws a procedure using shapes and arrows. It shows the order of operations, the choices that can be made, and the steps th…
08Flowcharts with filters: make every path finish a visit
A filtered flowchart adds another decision inside the loop. One decision asks whether work remains. The next asks whether the current c…
09Sanity of data: find problems before calculating
A well-written procedure can still give a wrong answer if its inputs are wrong. Sanity checking means asking whether the data have the…
10Basic data types: values and permitted operations
A data type describes two things: which values can be stored and which operations are permitted. A number-shaped label, a mark and a na…
11Subtypes: narrower rules for specific fields
A subtype narrows a broader type to suit a particular purpose. It can restrict both the allowed values and the operations. This makes t…
12Transform representations: dates, fractional marks and money
The way a value is displayed need not be the way it is stored. A useful representation makes the required comparisons and calculations…
13Records and lists: build structured data
Basic types describe individual values. A record bundles named fields into one structured item. A list gathers a sequence of items. Com…