Unit 23 - Aggregate Condition-Exploring States of Matter

In the liquids station, demonstrate the Rainbow Jar: slowly layer honey, corn syrup, washing-up liquid, coloured water, vegetable oil, and coloured rubbing alcohol in a tall jar. Pupils predict which liquid will sit where, then observe the distinct “rainbow” bands that form.

Fraction Analysis of Layers

• What to do: After layering the Rainbow Jar, pupils measure each layer’s height (in cm) and the total height. They then express each layer as a familiar fraction of the whole (e.g. “about ½”, “about ¼”, “about ⅓”, or nearest simple fraction)

• Why it works: Reinforces part–whole reasoning and comparing fractions without needing decimals.

• Extension: Ask “Which two layers together make about ¾ of the jar?” or “If we added another layer of the same size, how would the fraction change?”

• What to do: In pairs, pupils measure the jar’s total height and layer heights, then compare between groups. They note differences (e.g. Group A’s honey layer is 5 cm, Group B’s is 4 cm) and discuss why results might vary (pouring speed, accuracy).

• Why it works: Builds skills in measuring length, recording data, and discussing variation/error.

• Extension: Convert centimetres to millimetres or vice versa; calculate differences (e.g. 5 cm – 4 cm = 1 cm) and relate to fraction of total.

• What to do: Using measured heights, pupils draw a quick bar chart (vertical bars) showing each layer’s height. Alternatively, use squares on grid paper to represent each centimetre.

• Why it works: Introduces data representation: reading scales, drawing labelled axes, and interpreting which layer is tallest/shortest.

• Extension: Pose a question like “If the jar were twice as tall but proportions stay the same, what would the new bar heights be?” Leading to simple multiplication of measurements.

• What to do: Pupils sketch a scaled diagram of their Rainbow Jar on paper (e.g. 1 cm on paper = 2 cm actual). They calculate the scaled heights of each layer and draw them.

• Why it works: Practices ratio and scale concepts in a concrete context.

• Extension: Change scale (e.g. 1:3) or ask what happens if they want the drawing to fit a given space (e.g. total height must be 15 cm on paper).

Note: You can add a step where students use a mobile thermometer app (or a digital sensor app) to record the temperature of ice as it melts or water as it warms: ask the students to write down the melting point and boiling point readings in their model labels.  The students can pair a mobile app with a Bluetooth-capable digital thermometer probe to log temperature readings during the phase-change demonstration. Phyphox (with external Bluetooth sensor like NODE+). Limitation. Most apps require specific sensors (devices). 

This cooperative circle game suits all ages: ideally, 6–10 players hold hands in a circle while someone outside (or briefly stepping out) drops a balloon or soft ball into the ring; the group must keep it aloft using any part of their bodies without letting go of hands, preventing it from hitting the ground. Depending on player numbers and skill, use one or more balls or balloons—balloons fall slowly for an easier version, while adding extra balls or balloons raises the challenge.

A competitive team game using sponge noodles, balloons, and Frisbees: players split into two teams and use a play area about 10–15 metres between end zones with a central zone. One team stands in the centre, each holding a sponge noodle and balloon, and must keep their balloons aloft above head height; the opposing team, positioned in the end zones, throws Frisbees to try to knock down the balloons. A balloon hit or dropped below head height is out of play. Once all balloons are eliminated, teams swap roles, and the side that successfully gets more balloons across when attacking wins. For older players, a variation is to move balloons from one side to the other without being hit, or to use sponge balls instead of Frisbees.