Time Management & Productivity 5 min read

Double It Rule

The Double It Rule is a time management strategy where you estimate how long a task will take, then double that estimate to account for planning fallacy and unexpected complications.

Why time estimation is so difficult

Time perception involves complex brain processes that continue developing through adolescence. The planning fallacy—underestimating task duration—affects everyone but particularly impacts teens who lack experience and whose prefrontal cortex is still developing.

Research shows that people estimate based on best-case scenarios, ignoring typical complications. Students particularly underestimate homework time, estimating based on understanding rather than execution time. The Double It Rule provides external scaffolding for still-developing time perception abilities.

Kahneman and Tversky (1979) identified the planning fallacy as a cognitive bias where people underestimate task completion times despite knowing that previous tasks have overrun. Buehler et al. (2010) found that students underestimate assignment completion time by an average of 40%.

You're not alone

If your teen insists homework will take "just 30 minutes" then panics at 11 PM with hours left, or consistently runs late despite believing they have plenty of time, poor time estimation is the culprit. Many parents become frustrated by repeated underestimation despite experience proving otherwise. The teenage brain genuinely struggles with time perception. Families using the Double It Rule report less stress and better completion rates.

What it looks like day to day

Student

Your teen estimates their essay will take one hour, doubles it to two, and actually has time for revision rather than submitting rough drafts.

Parent

You suggest doubling the estimated getting-ready time, and your teen actually arrives at events on time without the usual rushing chaos.

Tiny steps to try

Implement the Double It Rule gradually with reflection and adjustment.

1

Estimation practice

Before tasks, estimate duration. Write it down. Compare to actual time. Build awareness of patterns.
2

Category multipliers

Some tasks need tripling (creative work), others just 1.5x (routine tasks). Develop personalized multipliers.
3

Buffer protection

Treat doubled time as non-negotiable. Resist temptation to squeeze in "just one more thing."
4

Backwards planning

Start with deadlines, work backwards using doubled estimates. [Calendar blocking](/the-parent-bit/finding-order-in-the-chaos-setting-up-calendars-for-kids) prevents overbooking.
5

Celebration of accuracy

When doubled estimates prove correct, acknowledge the win. Builds buy-in for continued use.

Why teens need the Double It Rule

Adolescents consistently underestimate task duration due to optimism bias, limited experience, and underdeveloped time perception, leading to chronic lateness and incomplete work.

Common time estimation errors:
• Forgetting setup and cleanup time
• Ignoring transition time between activities
• Assuming perfect conditions
• Discounting potential distractions
• Overlooking complexity
• Minimizing revision needs

The Double It Rule builds in buffer time for reality versus idealistic estimates.

References

Buehler, R., Griffin, D., & Peetz, J. (2010). The planning fallacy: Cognitive, motivational, and social origins. Advances in Experimental Social Psychology, 43, 1-62.

Kahneman, D., & Tversky, A. (1979). Intuitive prediction: Biases and corrective procedures. Management Science, 12, 313-327.

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Frequently Asked Questions

Won't doubling estimates waste time?

Extra time rarely goes unused. Teens can review work, get ahead, or enjoy guilt-free breaks. Rushing due to underestimation produces lower quality work and increases stress. "Wasted" buffer time is investment in quality and wellbeing. Most teens find they need the full doubled time more often than not.

What if my teen resists, saying doubling is ridiculous?

Start with tracking actual versus estimated times without doubling. Let data speak. Most teens are shocked by the discrepancy. Frame doubling as experiment: "Try it for one week and see." When they experience reduced stress and improved outcomes, resistance usually decreases. Sometimes calling it "realistic planning" works better than "doubling."