Engineering Practice: Explore Properties and Uses of Materials

Students come to our classrooms with a variety of experiences, knowledge, and skills. By being intentional and public about making observations, the teacher creates an environment where everyone can access the information they need to successfully design play dough made from flour, water, and salt. Having already observed commercial play dough, students can connect how the different materials may come together in a mixture that has the desired properties.

1. Students use common words to make scientific observations. This allows them to practice their language and try on new words. 2. Students work on their speaking skills by sharing their thinking out loud. 3. The teacher records observations on a chart, connecting written words with students’ spoken words. The chart becomes a word bank students can draw from when writing later in the lesson.

The sponges in the bag are dry, meaning they are not soft or squishy like a wet sponge in the kitchen would be. Therefore, the student stated they are “hard.” However, to be a good wrecking ball, a material must be hard and heavy enough to knock down blocks, which the sponge might not be able to do.

Allowing the student to test the material will help them gain first-hand knowledge of how the “hard” sponges work as a wrecking ball material. It also supports their agency in the classroom to make decisions. Before they test the sponges, ask students why they think that will be a good material for a wrecking ball. Ask them to explain why a hard material will work best. This will help students to connect the properties of the materials with their use in the design challenge. After they have tested the sponge, prompt students to share what they noticed from testing. Did the sponge work? What other materials would they like to try? Encourage students to test multiple materials and compare them. Which materials were better for a wrecking ball? Why do they think that?