What are realistic expectations for a toddler's attention span?

Short — commonly estimated at roughly two to five minutes per year of age for a focused task they did not choose, though attention on something self-chosen can be considerably longer. This means a three-year-old sitting through a twenty-minute activity is unusual, not delayed. Practical implications: keep structured activities brief, expect to repeat instructions, give one instruction at a time rather than a sequence, and do not interpret normal distractibility as a problem. Concern is warranted if a child cannot sustain attention even on things they enjoy, or if difficulties are affecting daily functioning.