Spider and Insect Detectives

Grade Level 1^st–2^nd

Lesson Overview

This lesson will introduce students to the differences between a spider and an insect. The students will participate in a collaborative group activity and complete individual Venn diagrams for assessment. In addition, there are some extension activities for review and enrichment.

Lesson

Set the Stage

The teacher will capture the students’ attention by telling the kids about a strange bug found in the classroom and asking for their help determining if it is an insect or a spider. Show the overhead Classroom Bug: Insect or Spider? (PDF – 143k). Ask the students to raise their hands for those that predict it will be an insect and those that predict spider. Tell the students you are going to investigate as a class.

Discussion

Tell the students that you did some research today and learned that a spider has 4 pairs of legs. Remember that a pair is two, so how many legs does a spider have if it has 4 pairs? Draw tally marks on board if needed for an illustration. Yes, that’s right, 8 legs in all. An insect has only 3 pairs of legs, or 6 legs in all. Spiders do not have wings; insects can have wings. Spiders have 2 body parts and insects have 3 body parts. Show the Body Parts (PDF – 460k) diagram on overhead. The teacher should point out the different body parts on a spider and on an insect. The cephalothorax and abdomen of a spider and the head, thorax, and abdomen of an insect. Spend some time discussing these parts. Insects have two antennae that help them smell. Insects sometimes have wings; spiders never have wings.

Spiders are called arachnids, which means it is a type of bug with 4 pairs of legs and a body divided into two regions. Scorpions, mites, and ticks are also arachnids. Spiders can produce silk and most of them make webs.

Spiders and insects are alike in some ways too. They both have hard, outer skeletons. They both have eyes (although the number does differ: insects have 2 eyes and spiders have 8 eyes). They both have a mouth and legs.

Do any of these facts help us determine if the bug I found is a spider or an insect? Yes, we have solved it! It’s a spider!

Group Activity

Tell the class they are ready to become Bug Detectives. Pass out the pretend Magnifying Glass (PDF – 269k) or real ones if you have them. Now, divide the class into groups of 4 so they can work together as Bug Detectives. Hand out one Bug Card (PDF – 241k) to each group and have them cut out the bugs on the worksheet. They will lay each bug down either under the insect column or the spider column of the Spider or Insect Chart (PDF – 482k). Walk around and make sure they are discussing and working together as a group. Check their work as you are walking around. Collect the bug cards and charts.

Individual Activity

Now, it is time for individual assessment. Hand out the Spider vs. Insect Venn Diagram (PDF – 75k) and instruct students to fill in at least 3 things they remember about a spider in the spider circle, three things about an insect in the insect circle, and three things that they have in common in the overlapping space. Use the Venn diagram overhead to point out where the facts will go in case students are not familiar with Venn diagrams.

Ask the students a final question: Is a spider an insect? They should overwhelmingly answer, ";No!"