In the must-read fourth book in the Alien in My Pocket series, Zack and his alien friend, Amp, learn about friction, deceleration, and how to soften a crash-landing in this hilarious new adventure.

When Zack McGee crashes his bike, he winds up stuck at home with his arm in a sling and his baseball season on the line. But it gets even worse when Zack realizes the reason why his brakes failed-his four-inch-tall alien houseguest, Amp, stole them for an experiment! Now Zack is stuck alone at home, woozy from pain medicine, and unable to do much of anything. Which makes him easy prey for his annoying little brother, Taylor, who’s determined to find out once and for what mysteries Zack has hidden in his pocket.

Like every book in the Alien in My Pocket series, On Impact! mixes Common Core-aligned science and safe, hands-on experiments with hilarious stories young readers will love.