While Lecturer at San Diego State University (1989-1990), he worked with Carol Robinson-Zañartu, Valerie J. Cook-Morales, and Colette Ingraham. He was influenced by them and learned the assessment and services for children within the environmental and multicultural context and by integration with ecological processes. For his interests in Rational Emotive Therapy (RET) in Counseling, he had an opportunity to be supervised by Albert Ellis. From Ellis, he learned how to serve people with focuses on resolving cognitive, emotional and behavioral problems and disturbances and enabling people to lead happier and more fulfilling lives. He applies and revised the RET to be useful and effective for Japanese clients by integrating RET with humanistic approaches.[4]
He has been providing psychological support for children in the affected areas by The Great East Japan earthquake as a coordinator for Child and School Support Team in the Japanese Association of School Psychologists,[6] as well as a leader of Psychological Support Team for Children in Fukushima Educational Board.[7] For this tremendous work, he was awarded "President's Award to Outstanding Contribution" from National Association of School Psychologists in 2012.[8]
In 2013, for memorizing his contribution in the field of school psychology for years, "Toshinori Ishikuma School Psychology Award", named after him was established in Japanese School Psychology Association (JSPA).[10]
Matsubara, T.; Fujita, K.; Maekawa, H.; Ishikuma, T. (1993). Japanese K-ABC: Administration and scoring manual. Tōkyō: Maruzen Mates.
Azuma, H.; Ueno, K.; Maekawa, H.; Ishikuma, T.; Sano, H. (1998). Japanese WISC-III Manual. Tōkyō: Nihon Bunka Kagakusha.
Ueno, K.; Fujita, K.; Maekawa, H.; Ishikuma, T.; Dairoku, K.; Matsuda, O. (2011). Japanese version of the Wechsler Scale for Children- IV. Tōkyō: Nihon Bunka Kagakusha.
Kaufman, A.S; Kaufman, N.L.; Fujita, K.; Ishikuma, T.; Aoyama, S.; Hattori, T.; Kumagai, K.;Ono, J. (2013) Japanese version of K-ABC-II Maruzenn
Wechsler, D.; Uemo,K.; Ishikuma, T; Dairoku, K.; Matsuda,.; Yamanaka, K. (2018) Japanese version of Wechsler Adult Intelligence Scale-IV. Nihon Bunka Kagakusha
Wechsler, D.; Uemo,K.; Ishikuma, T; Dairoku, K.; Matsuda,.; Nagoshi,N;Nakatani,I(2021) Japanese version of the Wechsler Scale for Children-V. Tokyo:Nihon Bunka Kagakusha.
Ishikuma, Toshinori (1999). School psychology : psycho-educational services by a team of teachers, school counselor, and parents. Tōkyō: Seishin Shobō. ISBN9784414301496.
Ishikuma, T.; Tamura, S. (2003). Introduction to team support by using Ishikuma-Tamura Support Sheet; School Psychology Practices. Tōkyō: Tosho Bunkasha. ISBN9784810033922.
Fukuzawa, S.; Ishikuma, T.; Onose, M. (2004). apanese School Psychology Association (ed.). Handbook of school psychology. Tōkyō: Kyoiku shuppan. ISBN9784316800608.
Ishikuma, T.; Ito, S. (2005). Live flexibly: Learning from Rational Emotive Therapy and stuttering. Tōkyō: Kanekoshobō. ISBN4760836071.
Toshinori, Ishikuma (2006). Psychology of helping and being helped learning from "Tora-san and Hama-chan": Six lessons to live flexibly. Tōkyō: Seishin Shobō. ISBN9784414403633.
Mizuno, H.; Ishikuma, T. (2009). Effective services in schools: forefront of school psychology. Kyōto: Nakanishiyashuppan. ISBN9784779503481.
Tsuge, M.; Ishikuma, T. (2013). Special needs education in senior high schools; 70 questions and answers for parents and teachers. Tōkyō: Kanekoshobō. ISBN9784760823772.
Mizuno, H.; Ishikuma, T.; Tamura, S.; Tamura, S.; Iida, J. (2013). Introduction to School Psychology. Kyōto: Mineruva Shobō. ISBN9784623063963.
Moon, S.; Ishikuma, T.; Kaufman, A. S. (1987). "Joint factor analysis of the K-ABC and McCarthy Scales". Perceptual and Motor Skills. 65 (3): 699–704. doi:10.2466/pms.1987.65.3.699. PMID3438113. S2CID25731766.
Ishikuma, T.; Moon, S.; Kaufman, A. S. (1988). "Sequential-simultaneous analysis of Japanese children's performance on the Japanese McCarthy Scales". Perceptual and Motor Skills. 66 (2): 355–362. doi:10.2466/pms.1988.66.2.355. S2CID145779459.
Kaufman, A. S.; McLean, J. E.; Ishikuma, T.; Moon, S. (1989). "Integration of the literature on the intelligence of Japanese children and analysis of the data from a sequential and simultaneous model". School Psychology International. 10: 73–183. doi:10.1177/0143034389103002. S2CID144715530.
Kaufman, A. S.; Ishikuma, T.; Kaufman-Packe, J. (1991). "Amazingly short forms of the WAIS-R". Journal of Psychoeducational Assessment. 9: 4–15. doi:10.1177/073428299100900101. S2CID143501659.
Ishikuma, T. (1991). "Introduction to cross-cultural communication in English". University of Tsukuba English Counseling: 59–68.
Valasquez, R.J.; Callahan, W.J.; Evans, D.; Ishikuma, T. (1994). "DSM-III-R training in master's-level counseling programs". Psychological Reports. 74 (3 Pt 2): 1331–1338. doi:10.2466/pr0.1994.74.3c.1331. PMID8084954. S2CID28940886.
Kaufman, A. S.; Ishikuma, T.; Kaufman, N. L. (1994). "A Horn analysis of the factors measured by the WAIS-R, Kaufman Adolescent and Adult Intelligence Test (KAIT), and two new brief cognitive measures for normal adolescents and adults". Assessment. 1 (4): 353–366. doi:10.1177/107319119400100404. S2CID143263242.
Ishikuma, T. (2003). "Policy and direction of development of counseling profession in Japan". Konvensi National Bimbingan Dan Kouseling: 18–22.
Jimerson, Shane R.; Oakland, Thomas; Farrell, Peter T. eds. (2007). The handbook of international school psychology. Thousand Oaks [u.a.]: Sage. pp. 217–227. ISBN9781412926690. {{cite book}}: |first3= has generic name (help)
Ishikuma, T.; Matsuda, O.; Ueno, K. S. (2016). "Intellectual assessment of children and youth in Japan: Past, present, and future". International Journal of School & Educational Psychology. 4 (4): 241–246. doi:10.1080/21683603.2016.1163711. S2CID147582780.
^Jimerson, S. (2007). Shane, R. (ed.). The handbook of international school psychology. Thousand Oaks [u.a.]: Sage. ISBN9781412926690.
^ abcKaufman, Alan. S (2009). Intelligent testing : integrating psychological theory and clinical practice. Cambridge [England]: Cambridge University Press. ISBN9780521861212.
^Ishikuma, T. (1989). In Japanese Association of Student Counseling (ed.). Invitation to Rational-Emotive Therapy (RET) from Albert Ellis. Tokyo: Kawashima Shoten. pp. 31–59.