Working out the order in which a figure has to be drawn

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What to assume they know

Every curve in these figures is part of a circle — a compass makes arcs, and an arc needs a centre and a radius decided before it can be drawn
Measuring and marking a stated length with a ruler
The idea that a drawing can be broken into parts that are drawn separately

What they should be able to do

Break a given figure into components and say what each one needs
Identify which part of a figure can be drawn without reference to any other
For a given arc in a figure, name the two things that must be settled before it can be drawn
Distinguish a length the problem fixes from a length the solver is free to choose
Explain what a rough diagram is for, and why it carries no measurements
Recognise a supporting line — a line drawn purely to locate something else
Say how to check a finished construction against the conditions it was supposed to satisfy

Where it usually goes wrong

"Drawing is a skill; either your hand is steady or it isn't." The freehand attempt on p.187 fails for everybody. What the instruments add is not steadiness but the ability to make a length exact and repeat it, p.189.
"You should start at the top left and work across." You start at whatever needs nothing else. In the House the walls come first and the apex last, p.211, because the apex is located from the walls.
"A rough diagram is a bad drawing." It is a deliberately unscaled one. Its job is to show which lengths are equal and which angles are known, so that the order can be worked out before accuracy costs anything.
"Every position in a figure can be calculated." Some cannot, and the book says so: for the arc in A Person and for the two eye centres, it asks for a good estimate, p.190 and p.215.
"Extra lines are mistakes." Supporting lines are part of the method, p.215.
"When the problem gives no measurement, the problem is incomplete." It means the answer is a whole family of figures, and you may pick one member. Wavy Wave and the two-square rectangle are both like this.
"Once it's drawn, it's done." The construction is only finished when the figure has been checked against the conditions it had to meet, p.210.

Questions to check understanding

Given a figure, list its parts in an order in which they could be drawn, and say why the first one is first
What has to be known before an arc can be drawn?
Draw a rough diagram for this construction and mark on it every equal length
Which measurements in this problem are given, and which are yours to choose?
Identify a line in this construction that is not part of the final figure
After completing the construction, state how you would check that it is correct
The chapter puts this question in the book's own words at p.211: in what sequence should the lines and the curve of the House be drawn?

Examples worth working on the board

A Person, p.190. The book prints the whole figure, then prints its pieces separately: on one side a circle with a short straight segment hanging below it, on the other a four-sided outline whose upper edge has been replaced by an arc curving inwards. Checked against p.190. The order that works: draw the four-sided outline, then settle the compass position for the arc, then the head. The book's stated difficulty is exactly the middle step — finding the position of the tip and the opening.
Wavy Wave, p.191. The problem states no length at all. The book chooses AB = 8 cm to have something to work with. Every other number in the figure then follows: X at 4 cm, compass opening 2 cm. Use this to separate given from chosen: choosing 8 cm is allowed, and choosing 12 cm would have been equally allowed, but once chosen it constrains everything after it.
Eyes, p.192, and the hint on p.215. The hint page shows two faint horizontal lines belonging to no part of the eye, and two marked points — one above the shape and one below — where the compass tip goes for the upper and lower arcs. Checked against p.215. The book's own point is that a construction may legitimately contain marks that get discarded.
The rough diagram for two identical squares, p.200. A rectangle with A, B, C along the top and F, E, D along the bottom, divided by one vertical line into two squares, with tick marks on the equal sides. No lengths on it. Checked against p.200. This is the first place the chapter shows a plan being drawn before the construction.
The rough diagram for the 60°/30° rectangle, p.205. A, B along the bottom and D, C along the top, with the diagonal AC drawn and 60° and 30° marked at A. Again unscaled. The very next line of the book asks in what order the parts should be drawn. Checked against p.205.
The House, p.211. The book states the first task as identifying the sequence in which the lines and the curve are to be drawn, and then works through it in four steps. Use this as the payoff for the whole topic: the same question §8.1 raised informally is now the stated method.
The closing check, p.210. After the last point of the rectangle is found, the book asks the student to verify that the finished figure satisfies R1 and R2 — the two rectangle properties from §8.2. A construction ends with a test, not with the last line.

Figures to have open

A Person exploded into its two components and then rebuilt in order. Redraw; do not reproduce the printed art.
A dependency diagram for one figure: boxes for the parts, arrows meaning "cannot be drawn until". This is the topic's central image and the book does not print anything like it, so it must be invented and clearly presented as an added way of stating the chapter's method.
The eye with supporting lines shown and then removed.
A rough diagram beside its finished construction, at visibly different scales, to make the point that the rough one is not meant to be accurate.
No photograph or dataset is required.

Where this sits in the book

NCERT Ganita Prakash, Class 6, Chapter 8 "Playing with Constructions", §8.1 "Artwork", pp.187–192 — the freehand instruction on p.187, the instrument question on p.189, the two components and the estimate advice on p.190, and the unspecified central line on p.191
§8.4 "An Exploration in Rectangles", p.200, for the first printed rough diagram
§8.5 "Exploring Diagonals of Rectangles and Squares", p.205 for the second rough diagram, p.209 for the trial-and-error passage, and p.210 for the closing check against R1 and R2
§8.6 "Points Equidistant from Two Given Points", p.211, where the sequencing question is stated as the first task
Hints A, p.215, for supporting curves
Summary, p.216, for the line on rough diagrams