A point fixes a location; a segment is the shortest route between two points

What to assume they know

Mathematics is the search for patterns *and* for why they hold: mathematics looks for a rule behind what is drawn, not only at the drawing
Recognising a straight edge from a curved one by eye
Reading a capital letter as a label rather than as a quantity
Comparing two paths and saying which is longer — no measurement required

What they should be able to do

State what a point determines and what it does not have
Explain why a sharper pencil gives a better model of a point but never a point
Label points on a figure with capital letters and read the labels back aloud
Describe a line segment as the shortest of the routes between two given points
Identify the end points of a segment and say whether they belong to it
Write the same segment two ways and justify why the order of the letters does not matter
Read a drawn figure and list the segments it contains
Say which marked points of a figure lie on one segment and which lie on two

Where it usually goes wrong

"A point is a very small dot." It is not a small anything — smallness is a property of the model, not of the point. Corrected by pushing the sharpening argument to its end: however fine the tip, the mark still has width, so the point is what the mark approximates rather than what it is.
"The line segment is the line I drew." Corrected by Fig. 2.1: several different drawn routes join the same A and B, and only one of them is the segment. Without the word shortest, "the segment AB" would not name anything in particular.
"Segment AB and segment BA are different because the letters differ." Corrected in §2.2 — both spellings name the same set of points. Flag here that rays will behave differently, so the student expects the contrast rather than being caught by it.
"The end points are the boundary, so they are outside the segment." The book includes A and B in the shortest path. Corrected by asking whether the crease stops just short of the fold's corner.
"Labels are decoration." Corrected by section 4: with three unlabelled dots there is no way to say which one you mean, and the whole rest of the chapter is statements about named objects.

Questions to check understanding

Name the line segments in a given open or closed figure, and count them
Given a marked figure, state which points lie on exactly one segment and which on two
Draw a rough figure to a written specification — for example, a line containing two named points but not a third
Explain in one line why a segment has a definite length but a line does not
Short-answer items on what a point has and has not, phrased as "state whether a point has length"
Figure-reading items that ask for five points, a line, four rays and five segments from one drawing (§2.4, p.16) — this topic supplies the segment half

Examples worth working on the board

The three named points (§2.1, pp.13–14). Three dots carrying the capital letters Z, P and T; the book reads each one out with the word Point in front of its letter. Use them only to make the case for labelling; the positions on the page carry no meaning.
The two drawings beside §2.2 (p.14). The upper one, which carries no figure number of its own, shows a rectangular sheet with a straight crease running from A at the top edge to B at the lower right. Below it sits Fig. 2.1 — several wandering routes drawn from A to B, arrows on each, the straight one among them; the caption and the body text both attach that label to the routes alone. The argument of the section is the comparison between the two drawings, so both are needed.
Fig. 2.4 (§2.4, p.16). A five-point open zig-zag, read left to right as L, M, P, Q, R. The segments in it are LM, MP, PQ and QR — four segments, not five, because the path is open. L and R each lie on exactly one of them; M, P and Q each lie on two. A point interior to the path is shared by the two segments meeting there, and the two ends are not.
Naming as an equality. AB and BA are two spellings of one segment. State it as a claim about the object, not about the notation, because §2.4 will immediately contradict the analogous claim for rays.
The idealisation figure the book does not print. A dot drawn at four magnifications, shrinking but never vanishing. This is an added visual for section 1; the book makes the point in words at §2.1, p.13.

Figures to have open

Both p.14 drawings — the uncaptioned crease on the folded sheet, and Fig. 2.1 itself, the family of routes from A to B. Redraw rather than reproduce; the geometry is standard, but the routes drawing is the section's whole argument and must not be simplified to one curve.
Fig. 2.4, the five-point zig-zag L-M-P-Q-R. Standard schematic; the shape is arbitrary, but the topology — open path, five points, four segments — is not.
Three named dots for section 4. Standard schematic.
No table, dataset or photograph is needed for this topic.

Where this sits in the book

NCERT Class 6 Mathematics (Ganita Prakash), Chapter 2 "Lines and Angles": chapter opening paragraph and §2.1 Point, p.13; §2.2 Line Segment, p.14
Exercise material drawn on: §2.4 Ray, Figure it Out Q2 (Fig. 2.4), p.16
Summary, p.54, for the settled wording of the point and segment entries
Forward pointer inside the chapter: §2.3 Line, p.14, which extends the segment