TY - CPAPER TI - Beginning Third-grade Students’ Manipulative-based Understanding of the Place-value Position Principle for Two-digit and Three-digit Numbers AU - Kaiser, Anna AU - Ufer, Stefan T2 - Proceedings of the International Group for the Psychology of Mathematics Education, Volume 1 PB - Psychology of Mathematics Education (PME) PY - 2026 SP - 731 EP - 738 SN - 2790-3648 KW - place-value understanding KW - place-value position principle KW - primary school KW - base-ten system KW - manipulatives UR - https://www.igpme.org/publications/RR_PME49/rr/kaiser-beginning-third-grade-students-manipulative-based-understanding/ ER -