A 9-year-old boy killed in a freak accident on his school’s playground in Melrose, Massachusetts, is being remembered as a determined child who loved skiing and had a bright future ahead. Zakaria Bel Qaid’s family announced his death on social media Tuesday, saying he was involved in a “crazy and unbelievable accident on the playground at his school where a tree from a neighboring property broke and fell on him while he was playing on the play s…