Sleep paralysis occurs as a person is moving into or out of REM (rapid eye movement) sleep, the deepest part of sleep. During REM sleep, the body is largely disconnected from the brain, effectively leaving the body paralyzed.
England and a few other countries start formal education at age 4 or 5. That's harmful and misguided.
Because education in the Netherlands is compulsory between the ages of 4 and 16 (and partially compulsory between the ages of 16 and 18), all pupils must attend high school. The high schools are part of the voortgezet onderwijs (literally: continued education).