Educational Insights Hot Dots Elapsed Time Math Cards Practice elapsed time with this interactive card set! Set includes 50 double-sided, fully-illustrated cards for 100 elapsed time problems. Includes problems in increments of 1 hour, half hour, quarter hour, 5 minutes, and 1 minute. Use as basic flash cards or add the Hot Dots Talking Pen (not included) for instant reinforcement. Touch the pen to an answer dot for positive reinforcement (correct responses) or gentle redirection (incorrect responses).