English-speaking preschoolers who knew letters but were nonreaders (M = 4 years 9 months; n = 60) were taught to segment consonant-vowel (CV), VC, and CVC words into phonemes either with letters and pictures of articulatory gestures (the LPA condition) or with letters only (the LO condition). A control group received no treatment. Both trained groups outperformed controls on phoneme segmentation, spelling, word reading, and nonword repetition posttests. LPA training enhanced children's ability to learn to read words with practice more than LO training. The favored explanation, consonant with the motor theory of speech perception, is that LPA training activated the articulatory features of phonemes in words as children practiced reading them so that grapheme-phoneme connections were better secured in memory. Results also suggested that phoneme segmentation training with letters improved phonological short-term memory. (Contains 3 tables and 3 figures.)