1.The grown-ups stood in for Kevin
2. Some roles were also played by a tennis ball
3. Hundreds auditioned to play Kevin
4. The house is real – and the family living in it stayed there
5. Joe Pesci stayed in character throughout
6. Joe Pesci nearly got set on fire on set
7. A high school gym was involved
8. The snow was (sort of) real
9. Robert de Niro could have played Harry