5. Periodic Table Shower Curtain
OK, bath accessories like this periodic table shower curtain aren't technically toys. But given that high schoolers seem to spend half their waking hours in the shower, might as well have them come out knowing the atomic mass of beryllium. Last we checked, chemistry teachers still require their students to know the periodic table, but we also like the playful reminder that learning can happen anywhere.
The bottom line: This accessory makes shower time productive.