In your last few sessions you made Scratch programs that used variables, loops, conditionals and events. Today you become the planner before you become the builder.
Here is the question: how do real programmers turn a vague idea ("I want a quiz game") into something they can actually build? They use four named thinking steps. By the end of today you will have planned a build of your own with those four steps and started making it in Scratch.
Quick recall to settle the class: ask one student to name a Scratch block they used last time and what it did. Keep it to a minute.
Today the headline is the thinking, not the code. Reassure students that they already have the Scratch skills; what is new is naming how they break a problem down.
Computational thinking has four named steps. We will use them on a real build today, so learn the names now:
Turn to your neighbour for 30 seconds: say one of the four steps back in your own words. Then we will keep going.
Worked example: a simple capital-cities quiz round. Here is each step on one line:
Predict before you plan: pick one build idea now (an animated scene, a quiz round, or a simple chase) and predict which of the four steps will do the most work for that idea. Hold that thought.
Say the four step names verbatim and write them where the class can see them all lesson. Students will be asked to name them aloud during the build.
Use the 30-second neighbour turn as a planned interaction break so the less confident students speak before any device work begins.
The worked capital-cities quiz is the model: walk the one-line list slowly so students see each named step applied to one concrete idea. The common misconception is that these are separate stages done once; in practice you loop back through them. Say so.
Offer three build ideas (animated scene, quiz round, simple chase) so no one stalls choosing. Keep abstraction concrete: it just means "leave out what does not matter yet".
Open your saved Scratch project area the class way (the way your teacher has shown you to open and save work in this room). If your earlier work is missing, ask your teacher or start a fresh project; you only need a clean stage today.
Choose one build idea: an animated scene, a quiz round, or a simple chase. Then work through the four steps on paper or in a shared doc. Keep the first three steps short and quick, the only one that needs full detail before you build is the algorithm for part one.
Circulate and make students say the step name as they work: "which step are you on right now?" That is the whole point of the lesson.
Note on 'the class way': this placeholder must match your established open/save routine for this group (network drive, shared folder, Scratch account, etc.). Replace it with the concrete instruction before delivery so self-directed students are not stuck.
Make the detailed-algorithm shortcut explicit: only part one's algorithm needs full numbered detail before building, so quicker movers reach Scratch sooner. Default the lower third onto the pre-filled planning template (three of four steps pre-filled) so they spend their time on the algorithm and the build, not on copying headings.
Keep going and build the next parts of your plan in Scratch. As you work, name out loud or in your notes which of the four steps you are using at each moment.
What done looks like:
If something breaks, use the debugging routine: read the symptom, find the block, form a hypothesis about why, test your fix, and revert it if it was wrong. Fix one thing at a time.
This is independent application, and it now has a realistic twelve-minute window so the 'what done looks like' criteria are reachable for most students.
Resist solving bugs for students; prompt them through the named debugging routine instead. If a student is still finishing part one, the second working part can carry into the next session or homework, but most should reach two parts here.
Close by reminding everyone to save the class way before the recap, projects continue in the next sessions and shared-device storage will not survive. Save your project now, the way we save in this class.
Hands up: who got at least one part working? What broke, and how did you spot it?
Now name the four steps against what you actually did today. Decomposition was your list of smaller parts. Pattern recognition was every time you noticed something repeating and reused it instead of copying. Abstraction was every time you left something out to keep version one simple. Algorithms was your numbered plan that the Scratch blocks followed. The big idea: the planning made the building easier, you were not just guessing with blocks.
Take two or three quick examples from the room and label them aloud with the correct step name. The goal is for students to hear the four terms attached to their own work, not in the abstract.
You're previewing this lesson. Get full access to this lesson and hundreds more — each one ready to teach, with interactive activities, printable resources and pupil progress tracking built in.