Lyric discussion by ShadowCal 

Cover art for Nanobots lyrics by They Might Be Giants

I think this song is about growing up, throughout three generations. The first chorus revokes the idea of an older person telling a father how to raise his child. Instructions, corresponding to each stage of childhood. Grow the Nanobots up Grow them in the cracks in the sidewalk

Don't spend too much when they're a baby, because you'll run out. Rather, give them enough room to grow, and save what you can.

Wind the nanobots up Wind them up and ask them a question

Let your children think for themselves, ask their opinion.

Raise the yellow bots up Raise them up and make them respect us

Don't let your teenager take control of your family, gain their respect.

Wind the marching bots up Wind them up and wish them away

Let your child conform for now, and don't break down because they have to leave for college.

The first verse gives the child's (very fast) account of growing up, starting as a baby, and growing to a father with a child by the end(tiny figure testing limbs).

The second chorus is the original father's advice, somewhat present in the second father's mind, thus it's brevity. The current father is panicking, remembering the advice, but just barely.

The second verse is about the second child growing up. The sun is rising in the wrong place=Waking up early to help the baby. I would decorate the room but there's no more space=The lack of space due to the child. All I see is pictures of matchstick men=Childish drawings from the kid. I turn my back for two minutes and they've grown again=When the child seems to grow in a matter of seconds. "My, you've gotten so tall" comes to mind. Rearranging beds=Either masturbation or needing a new bed because of growth. Eating what's available=Teenager in a nutshell In some hand-me-downs=when clothes shopping isn't available, have some older clothes. Making do with leftovers=Home alone during adult trips, and can;t make food for themselves. Bunking up, sharing comic books=The moments of childhood before highschool graduation. Sitting three-deep in each other's laps=Sex/Adulthood In a van stacked up on other vans=Driving away to college Riding on the tidal wave where they=Sex

And the final chorus is the second father giving advice to his children, who repeat the advice back, adding his own for the situation.

My Interpretation