Build the key vocabulary of Seawater Properties and Salinity with this printable picture flash card set for Grade 4 science, aligned to Virginia SOL 4.7. It covers 12 essential terms, from Seawater mixture and Dissolved salt to Salt left behind. Each term comes as a picture-and-word card and as a picture card with a clear, full-sentence definition, and two labeling worksheets let students show what they know.

What students practice

• Seawater mixture: Seawater is a mixture of water, dissolved salts, dissolved gases, and other materials found in the ocean.
• Dissolved salt: When salt dissolves, it spreads through water so its grains can no longer be seen with our eyes.
• Salinity: Salinity describes how much salt is dissolved in water; saltier water has a higher salinity than less salty water.
• Dissolved oxygen: Many marine animals use oxygen dissolved in seawater, taking it into their bodies through structures such as gills.
• Evaporation: When ocean water evaporates, water enters the air while most dissolved salts remain behind in the ocean.
• Rainfall: Rain adds fresh water to the ocean surface and can lower salinity by mixing with the salty water.
• River runoff: Fresh water flowing from rivers into the sea can make nearby coastal water less salty than open ocean water.
• Melting ice: Melting ice adds fresh water to nearby seawater, lowering its salinity by spreading the dissolved salts through a larger amount of water.
• Water temperature: Ocean water temperature varies with location and depth, affecting the conditions experienced by plants and animals living there.
• Fresh water: Fresh water contains much less dissolved salt than seawater and enters oceans through rivers, rainfall, and melting ice.
• Fair comparison: To compare salinity fairly, use equal amounts of water and measure dissolved salt with the same method.
• Salt left behind: Evaporating a small seawater sample can leave salt crystals behind, providing evidence that clear seawater contains dissolved materials.

What’s included (11 pages)

• 12 color picture-and-word cards
• 12 picture–term–definition cards (4 pages)
• 12 black-and-white picture-and-word cards for low-ink printing or coloring
• 2 picture-labeling worksheets: students write the matching term for each picture (with Name and Class lines)
• Answer key (1 page) for the labeling worksheets

How to use it in class

1. Print the color cards (or the black-and-white set to save ink), cut them apart and laminate them to reuse.
2. Introduce the words with the picture-and-word cards, then use the definition cards to talk about what each term means.
3. Play quick games: show a picture and ask for the term, read a definition and ask which card it matches, or sort the cards into groups.
4. Use the labeling worksheets as an exit ticket, homework or review, and check them with the answer key.
5. Put the cards in a word wall or science center for independent practice.

At a glance

• Grade: 4
• Subject: Science (Seawater Properties and Salinity)
• Standard: Virginia SOL 4.7
• Pages: 11
• Format: Printable PDF; instant digital download after purchase