The Concepts: Students will learn how things grow and change. After discussing life cycles, children will examine how tadpoles grow and change into frogs and how mealworms grow into black beetles. Children will learn how to use a hand lens as they get up close by holding tadpoles found in containers of water at their table. They will also have a chance to see tadpoles with legs as they transition into frogs. In weeks to come, the mature frogs will be seen by the students.
Find tadpoles in local ponds and put them in the pond water in plastic shoe boxes. Have test tubes or small water bottles on hand for children who do not want to touch the tadpoles. You will also need hand lenses.
Frogs start out as tiny tadpoles. As they grow, they change. First they start out as a tiny egg, then they look like a little fish with a tail. As they grow, they develop two front legs. When the tail gets long and falls off, they will grow two more legs in the back. Soon, they will grow and turn into a frog. (Show photos of the stages of development).
Demonstrate by making your hand into a cup and gently scoop up some tadpoles. Remind the children that the tadpoles are living things and should be handled carefully. After having the tadpole in your hand for a couple of seconds, return them to the water. Be sure before the children touch the tadpoles they wash their hands as to not get the tadpoles sick!
One child is apprehensive about touching the tadpole and views it using a test tube. The other child uses a hand lens to get a closer look.
View the video for this activity here.