S1·E26 Termite Towers

When Sally and Nick can't keep their block tower from toppling over, The Cat in the Hat takes them to meet expert tower builders: the termites who, after shrinking down to bug-size, learn from Terry, the termite, how to build a tower that doesn't wiggle (not even wobbling at the same time). However, Raymond, the mole-rat keeps knocking over the termite mound... with some engineering tips from a termite, Sally and Nick can build their block tower higher than before as expected.