Lizards, and Geckos, and Toads...oh my

The boys love trying to catch all of the above.  We usually let them keep them overnight and then they have to release them.  We did have 2 toads, 1 green anole, and 1 gecko in 1 tank for a few weeks.  We bought lots of crickets to supplement their diet.  We then let them all go.  The boys are hankering to have pet any of the above now.  We cleared out a rotten log pile in our back yard and the boys caught 3 geckos and 1 toad.  There were also grub worms (nasty looking creatures) and lots of giant cockroaches in the pile.  We saw 1 salamander, but it was too quick for us.  Yesterday I was clearing out boxes in front of our garage and there was a salamander.  Joseph managed to catch it.  Today the boys were playing outside and they saw a baby toad.  Samuel caught it.  Now the boys really want to keep them.  I told them we would have to see.  We do have 2 terrariums, but I don't know if I want them to have more pets.  We already have 2 guppies that won't die.  Joseph's 1st grade teacher gave them to him.  Anyways.  I guess as long as they don't sneak them into the house and put them in a dollhouse which then gets knocked over by grandma as she cleans thus causing about 30 toads and frogs to escape into the house, then we are okay.