The points that are the same distance from two given points

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What to assume they know

Constructing a rectangle from one side and a diagonal — a point found where a circle crosses a line
Every curve in these figures is part of a circle — a circle is every point at a fixed distance from its centre
Working out the order in which a figure has to be drawn — working out the order a figure has to be drawn in
The two properties that define a rectangle, and the one more a square needs — the square conditions, for the closing question

What they should be able to do

Identify, in a figure to be recreated, which point cannot be drawn immediately and why
State the two conditions a point must satisfy to be the apex of the House
Locate a point at a stated distance from each of two given points, using arcs
Explain why two equal circles through two given points cross in two places
Choose the correct one of the two crossings for the figure being built
Draw an arc through two points from a centre already constructed
Recognise the same technique in a different problem, and reuse it
Construct a 4-sided figure with all sides equal that is not a square

Where it usually goes wrong

"Equidistant from B and C means halfway between them." The midpoint is one such point, but the apex of the House is not on BC at all. Every point on the line running perpendicularly through the middle of BC is equidistant from the two — a whole line of them.
"One circle should be enough to find A." One circle gives every point 5 cm from B, which is infinitely many. The second circle is what cuts that down.
"Two circles meet at a point." Two overlapping circles meet at two points. The chapter's own p.213 figure shows both. Which one you want is decided by the figure, not by the arithmetic.
"You could just measure 5 cm up from the middle of the walls." That is not where A is — it is 5 cm from B and from C, not 5 cm above the midpoint of BC. The two are different points, and the difference is visible on the page.
"The roof is a half circle." It is a much shallower arc than that; the two ends are only 5 cm apart while the radius is also 5 cm.
"A 4-sided figure with four equal sides has to be a square." The last task of the chapter exists to break this, and the tool for building the counterexample is the same two-arc move.
"The door's position is part of the problem." Its width and height are given; where it stands along the bottom wall is not.

Questions to check understanding

Recreate the House, with every border line 5 cm (the chapter's own p.211 task)
Construct a bigger house with all sides 7 cm (asked at p.215)
Locate a point 6 cm from each of two given points 8 cm apart, using arcs only
How many points lie 5 cm away from B and also 5 cm away from C? Where are they?
Rebuild the three §8.1 artworks using the House technique (asked at p.215)
Is there a 4-sided figure with all sides equal that is not a square? Construct one (asked at p.215)
Two points are 12 cm apart. Can a point be 5 cm from both? Explain

Examples worth working on the board

The House, p.211. Checked against p.211. The walls are three sides of a square: B at the top left, C at the top right, D at the bottom left, E at the bottom right, with BD, CE and DE each 5 cm. A is the apex above, joined to B and to C by lines that are also 5 cm each. The line BC is not drawn — an arc bulging downwards from B to C takes its place. Inside the walls, standing on DE, there is a door 1 cm wide and 2 cm tall. The chapter dimensions the door's width and height and does not dimension how far along DE it stands; that is left open.
Step 1, p.211. The walls and the door go down first, because nothing about them depends on anything else. Checked against p.211.
The two conditions on A, p.212. A must be 5 cm from B, and A must be 5 cm from C. Neither one alone is enough. The chapter says explicitly that this is the same situation as locating B in the previous section, and gives the page reference itself.
Steps 2 and 3, pp.212–213. A circle of radius 5 cm centred at B, then a circle of radius 5 cm centred at C. Checked against p.213, where both circles are drawn in full and both of their crossing points are visible — one above the walls, one down among them. The one above is A.
Why there are two crossings. BC is 5 cm and each radius is 5 cm, so each circle passes exactly through the other's centre, and the two overlap heavily. Whenever two circles of equal radius overlap like this they meet on both sides of the line joining their centres. The chapter draws both crossings without commenting on the second.
Method 2, p.213. Only the parts of the circles near the crossing were needed, so the chapter redoes it with two arcs. Same point, less ink — exactly the economy §8.5 introduced on p.210.
Step 4, p.214. A is now the centre of the last arc: open the compass to 5 cm again and draw from B round to C. Because A is 5 cm from both, the arc passes through both. Checked against p.214.
What the roof turns out to be. AB, AC and BC are all 5 cm, so the three points sit at the corners of a triangle with three equal sides, and the angle at A is 60°. The roof is therefore a sixth of a circle of radius 5 cm. The chapter prints none of this; supply it to the explanation as a reason the roof looks the way it does, marked as an extension.
The closing tasks, pp.215–216. A bigger house with every side 7 cm; then rebuilding the three §8.1 artworks — A Person, then Wavy Wave, then Eyes — with the House technique; then a 4-sided figure with all sides equal that is not a square. The hint on p.216 supplies the start of the last one: two 5 cm sides meeting at a corner that is not a right angle, and a fourth point to be found 5 cm from each of the two free ends. That is the House move again. Checked against p.216.

Figures to have open

The House, complete, with B, C, D, E, A labelled, every 5 cm marked, the door at 1 cm by 2 cm, and the roof drawn as an arc rather than a straight line. This is the topic's anchor image.
The two-circle figure with both crossings visible. Essential — the second crossing is a section of its own.
The two-arc version beside it.
The 4-sided figure with four equal sides and no right angles, built by the same two arcs, with the square beside it for contrast.
Optional extension figure: the line of points equidistant from B and C, built by repeating the two-arc move at several different radii. Not in the book; clearly not in the book.
No photograph or dataset is required.

Where this sits in the book

NCERT Ganita Prakash, Class 6, Chapter 8 "Playing with Constructions", §8.6 "Points Equidistant from Two Given Points", pp.211–214 — the House and Step 1 on p.211, the two conditions on A and Step 2 on p.212, Step 3 with both methods on p.213, and Step 4 with the roof arc on p.214
§8.6, p.215, for the three closing Construct items, and Hints B, p.216, for the equal-sided figure
§8.5, p.209, which §8.6 cites by page as the same idea
Summary, p.216, for the circle, the centre and the radius