PALS - Administration Procedures

Tadpoles

Administration Procedures

Contributed by: Assessment of Performance Unit (APU)

Description:

Students examine tadpoles at various stages of development.

Questions in the observation category assess pupils' ability to use a variety of senses to observe data in a certain way- a scientific way. All observing is selective and guided by a purpose. The general purpose in this test is that shared by scientists: discerning regularities, similarities and differences, patterns of various kinds and significant or systematic changes with time.

The assessment reflects a view of observation as the collection and interpretation of real data where little or no initial filtering out of detail has been made. For this reason observation is tested by a variety of practical tasks.

This task is designed to take students approximately 15 minutes to complete.

Overall Task Content Area:

Life Science

Specific Knowledge Areas:

Structure and function in living systems

Performance Expectations:

conducting investigations
using equipment
gathering, organizing, and representing data
formulating conclusions from investigational data

National Science Education Standards:

8 A SI 1: Abilities necessary to do scientific inquiry: Grades 5-8
1.4 Develop descriptions, explanations, predictions, and models using evidence. Students should base their explanation on what they observed, and as they develop cognitive skills, they should be able to differentiate explanation from description -- providing causes for effects and establishing relationships based on evidence and logical argument. This standards requires a subject knowledge base so the students can effectively conduct investigations, because developing explanations establishes connections between the content of science and the contexts within which students develop new knowledge.

8 C LS 2: Reproduction and heredity: Grades 5-8
2.5 The characteristics of an organism can be described in terms of a combination of traits. Some traits are inherited and others result from interactions with the environment.

(Use the"hot" link on the PALS home page to check the full text of related National Science Education Standards, if desired.)

National Council of Teachers of Mathematics:

PS2: Solve problems that arise in mathematics and in other contexts:
Grades 6-8

General Instructions to the Teacher:

This task is designed to take students approximately 15 minutes to complete.

Students will be working individually during this exercise.

Students should be ready to work as soon as the period begins.

Materials for "Tadpoles":

5 tubes labeled P, Q, R, S and T containing tadpoles at different stages of development

P = young frog -- complete tail absorbed
Q = first stage tadpole showing external gills
R = 2 hind legs; alimentary canal "coil" visible
S = no legs; alimentary canal, visible mouth
T = frog, 4 legs, tail approximately one and a half times body length

1 hand lens
1 piece of display paper

Advance Preparation:

Obtain tadpoles at different stages of development
Place tadpoles into tubes and label accordingly

Safety:

Be careful.
Teachers and students should always exercise appropriate safety precautions and utilize appropriate laboratory safety procedures and equipment when working on science performance tasks.