TY  - CPAPER
TI  - Which Item Characteristics Drive the Difficulty of Mental Addition and Subtraction Tasks
AU  - Sommerhoff, Daniel
T2  - Proceedings of the International Group for the Psychology of Mathematics Education, Volume 1
PB  - Psychology of Mathematics Education (PME)
PY  - 2026
SP  - 1379
EP  - 1386
SN  - 2790-3648
KW  - arithmetics
KW  - task design
KW  - difficulty-generating item characteristics
KW  - primary school
UR  - https://www.igpme.org/publications/RR_PME49/rr/sommerhoff-which-item-characteristics-drive-the-difficulty-of-mental-a/
ER  -