Make science fun with hands-on activities that encourage experimentation, observation and analysis. These durable plastic test tubes include leak-proof caps, so there is no worry about breaking or spilling. Includes 5 plastic test tubes, 5 screw caps and 5 double sided activity cards. The five activity cards include simple science experiments that are easily adaptable for multiple grade levels. Each test tube holds up to 35 mL (about 1 oz.). Recommended for ages 5 and up with adult supervision.