--- title: "Comparing Capacity" description: "Compare how much containers can hold and how much water is inside them. Describe containers as full, empty, half full or quarter full." canonical: https://lightmysky.com/learn/mathematics/comparing-capacity-mt_zkFbMLpu3U source: https://lightmysky.com/learn/mathematics/comparing-capacity-mt_zkFbMLpu3U.md retrieved: 2026-11-12 --- > **Agent view.** This is the Markdown twin of the page, for tools and assistants. > When to use this site, and the call that answers each job: https://lightmysky.com/agent-instructions.md > API description (OpenAPI 3.1): https://lightmysky.com/openapi.json · Authentication: https://lightmysky.com/auth.md > Pricing: https://lightmysky.com/pricing.md · Catalog: https://lightmysky.com/llms.txt · Full catalog: https://lightmysky.com/llms-full.txt > Every machine-readable file on this domain: https://lightmysky.com/.well-known/ai-catalog.json > Ask for Markdown with `Accept: text/markdown`, a `.md` address, or `?mode=agent`. # Comparing Capacity Compare how much containers can hold and how much water is inside them. Describe containers as full, empty, half full or quarter full. Subject: Mathematics · Area: Measurement · Ages 4 to 6 Page: https://lightmysky.com/learn/mathematics/comparing-capacity-mt_zkFbMLpu3U ## Ready when they can - Compare two containers and say which holds more/less - Use 'half full' and 'quarter full' to describe a container - Solve practical problems like 'Which cup has more water?' ## Lesson: Full, empty, and in between Capacity is how much a container can hold when full. Empty means nothing is inside. Full means it holds as much as it can. Pouring water out changes the amount inside. If the container stays the same, its capacity stays the same. **Example.** These bars show water amounts on the same scale. They do not show cup heights. A taller bar means more water. Equal-height bars mean equal amounts. Cup B's bar is taller, so Cup B has more water. These bars do not show how much either cup can hold when full. A cup's shape alone does not tell you how much water is inside. Empty cups given equal amounts without spills contain equal amounts, even if their shapes differ. Bars showing water amounts do not tell you how much the cups can hold when full. For same-size cups, the fuller cup has more water. A shaded bar can stand for how much of a container's capacity is filled. It is not a picture of the water's height. Half full means half the amount that fits. Quarter full means one of four equal amounts. Two of four make half. All shaded means full; none shaded means empty. *(drawing: For same-size cups, quarter full has less water than half full. Half full has less than full. Count the cups that match a comparison.)* With an adult, use two empty containers that each fill exactly with whole small cupfuls. Use the same full small cup each time. Pour without spills and count each cupful once. More cupfuls to fill means greater capacity; equal counts mean equal capacity. If the last pour needs only part of a cupful, use the pouring test below instead. A cupful diagram has one equal space for each full small cup that fits. Count filled spaces to find cupfuls already poured. Count empty spaces to find cupfuls still needed. A quarter is one of four equal amounts. Half is half of the equal amounts. **Example.** An adult starts with Cup A full and Cup B empty. They pour A into B and stop when B fills or A empties. They do not spill. Water left in A means A can hold more. Space left in B means B can hold more. If B fills just as A empties, their capacities are equal. **Recap.** Capacity is how much fits when full. Compare the water inside separately from how much the containers can hold. *Lesson, questions and flashcards written for this dataset.* ## Practice 17 questions on this page, each with its working shown. ## Needs first - [Measurable attributes of objects](https://lightmysky.com/learn/mathematics/measurable-attributes-of-objects-mt_NtJYlJdUe9) ## Opens up - [Capacity and volume](https://lightmysky.com/learn/mathematics/capacity-and-volume-mt_4lp_b5Pzik)