Various types of samples, including plastic foams, elastomers, and hollow-shaped plastics, are evaluated by both high-speed impact tests and the static compression tests. We found that the high-speed impact tests together with proper data analyses are very effective in evaluating Energy-Absorbing(E/A) properties of various materials. Analyses from the data obtained from those tests, estimation of E/A properties for different types of samples from the compression data should be avoided and the compression data are effective only among the same type of samples. With the high-speed impact tests, plastic foams and hollow-shaped plastics showed excellent head protection properties. Foamed plastics, which can be easily applied to interior trim parts, are focused on and some typical plastic foams are additionally tested under various conditions. Comparison of those test results to actual vehicle tests, design guidelines in applying plastic foams to head protection trims are introduced as final conclusion.