noun
mischievous age; age when children are full of mischief
Refers to a stage in childhood when kids are especially playful and prone to pranks; often used with a nostalgic or affectionate tone.
うちの子は今、いたずら盛りで、毎日何かやらかしてます。
My child is at that mischievous age now and gets into something every day.
いたずら盛りの小学
Elementary school kids at their most mischievous are running around the park.