STC Plant Growth and Development Lesson 13: Making a Brassica Model Option A Kennewick School District

Overview At this point in the unit, students have studied the Brassica flower and the bee in depth. During the next two lessons, students will have a chance to apply what they have learned by making models of both the flower and the bee. Model-building offers an opportunity to incorporate a number of other skills, such as planning, measuring, cutting, assembling, and organizing parts. The more proficient students are at these skills, the more accurate and aesthetically pleasing their models will be. This is a hidden slide for teacher information. STC Plant Growth and Development Lesson 13A: Making a Brassica Model

Lesson Objectives  Students apply skills they have learned to construct an accurate model of the Brassica.  Students work together on a group project. This is a hidden slide for teacher information. STC Plant Growth and Development Lesson 13A: Making a Brassica Model

Background Making models is a combination of science, technology, mathematics, and art. A model is a useful vehicle for illustrating small structures, such as those found in a flower or on a bee. A set of flower and bee models can be used to dramatically demonstrate their mutually beneficial relationship. By now, students have had a great deal of practice making observations. Those skills will come in handy as they try to replicate reality in the form of anatomically correct models. As much as possible, encourage students to design and build their own models based on their own observations. The plans described in this lesson are meant to serve only as starting points, not as blueprints. This is a hidden slide for teacher information. STC Plant Growth and Development Lesson 13A: Making a Brassica Model

Background (cont.) There are two different options suggested for making Brassica models in this lesson. Option A is the easier of the two. Option B is much more challenging. Also provided are two separate lists of materials and directions, a style that is different from the usual format of the lessons in the unit. All other elements in the lesson are the same. The models constructed in this lesson can be used in a dramatization of cross-pollination and interdependence. (See Lesson 14 for a sample script.) For this reason, the size of the models is important. You want them large enough to be seen across the classroom, yet small enough for students to manipulate. Sets of models (ideally, one bee to two flowers in order to show cross-pollination) should correspond roughly in size. This is a hidden slide for teacher information. STC Plant Growth and Development Lesson 13A: Making a Brassica Model

Procedure 1. Group students into cooperative work teams, and give them time to brainstorm about:  What the model should look like  What materials they should try to collect (Encourage recycling!)  What each member of the team will be responsible for 2. Hold a group discussion to help students finalize their plans for their models. Encourage them to develop their own models. To give everyone a head start, two sets of instructions fro making Brassica flower models are given. Option A includes instructions for making only the Brassica blossom. Option B includes instructions for making the whole plant. This is a hidden slide for teacher information. STC Plant Growth and Development Lesson 13A: Making a Brassica Model

Materials list—Option A For petals:  4 yellow styrofoam meat trays OR  1 plastic milk jug painted yellow OR  Cardboard painted yellow For anthers and pistil:  1 styrofoam meat tray OR  1 Plastic milk jug OR  Cardboard STC Plant Growth and Development Lesson 13A: Making a Brassica Model To hold pistil and anthers:  1 styrofoam or paper cup  4 brass fasteners  1 stapler  1 pair of scissors  Tempera paint and brush

Directions  1.Trace and cut four yellow petals.  2.Attach petals to each other as shown. Staples work well for thin materials, but brass fasteners are better for styrofoam or cardboard. STC Plant Growth and Development Lesson 13A: Making a Brassica Model Figure 13-2 Attaching the petals

Directions  3. Trace and cut one pistil, four tall anthers, and two short anthers. One idea is to glue sand to the anthers to simulate pollen, then use glitter to make the stigma glisten. STC Plant Growth and Development Lesson 13A: Making a Brassica Model

Directions  4.Staple the anthers to the pistil.  5.Cut a slit in the bottom of the styrofoam or paper cup. Poke the bottoms of the pistil and anthers through the slit. STC Plant Growth and Development Lesson 13A: Making a Brassica Model Figure 13-4 Putting the flower together

Directions  6.Force the cup into the space in the center of the four petals. The blossom is complete. You may hold it by the cup to move it. This type of model needs support, such as an empty coffee can, in order to stand. STC Plant Growth and Development Lesson 13A: Making a Brassica Model

Clean up and put all supplies where they belong. STC Plant Growth and Development Lesson 13A: Making a Brassica Model

Critique another group’s model for accuracy. Think about:  Does it have the correct number of petals and anthers?  Is only one pistil shown?  Are the parts in the right places?  Has the model been done neatly?  Is it attractive?  How much effort does it show? STC Plant Growth and Development Lesson 13A: Making a Brassica Model