I printed out frog coloring pages (you can google it.) Look at google images and noted the wide variety of colors frogs can come in, and then color the pic.
Discuss where you would find frogs, and where you find those beautiful colored frogs we find on google images. Map printouts are your friend.
Print out the life cycle of a frog, and go over it. Print out a 2nd one, and cut it into separate cards to be placed in the correct order.
Focus on the letter F....seriously, Three has a mental block about this letter, so we keep visiting it. Someday.
You could do color mixing here as well: blue/yellow to make green frogs.
Rhyme: Five Speckled Frogs! (I love this rhyme...shhh don't tell.)
Lily Pad craft: I cut out a green circle, used a coffee filter and let them paint the middle (or all of it in Three's case) yellow. After the coffee filter dries, glue the flower onto the lily pad. These turned out cute.
And, we may do the tadpole craft from notimeforflashcards (one of my FAVORITE sites): http://www.notimeforflashcards.com/category/frogs There are other good ideas, you should check it out. :)