Objective:
The students will use manipulatives to complete addition and subtraction problems involving the number 8.

Materials

• Small pieces of clay or Play Dough.  Each student or pair of students should have enough to make a 1-2" ball.

• Eight toothpicks per student or pair of students.

• Spider Math Worksheet

Procedure

1. Give each student, or pair of students, a piece of clay and 8 toothpicks.

2. Discuss how spiders have 8 legs.  

3. Have the students roll their clay into bodies for the spiders.  They may want to roll 2 pieces - one for the head and one for the body.

4. The toothpicks will serve as the legs.  The teacher may give the students age appropriate math problems.  The students should then use the legs to figure out the answers.  For example, "Your spiders only have 4 legs, then they grow 4 more.  How many do they have altogether?" "Your spiders have 8 legs, 2 fell off.  How many are left?"   Older students may work with adding 3 numbers together, or even multiplying by 8 by joining their spiders with other students'.

5. The Spider Math Worksheet may be used to record some of the problems the students are given, or for recording their own problems. 

Other Lesson Ideas

1. Have a measurement lesson in which comparisons are made between spiders which are as small as pencil points, all the way up to tarantulas which can have a 10" leg span.  The students may also use 10" spans to measure distances.  This would be a good lesson in counting by 10's.