Magnetic marbles as teaching aids - ACS Publications

school. Upon LSRP departure teachers typically discuss with their students the ... “Los Angeles Unified School District Ethnic Survey Report”, Pub...
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of matter, with regard to the liquid nitrogen, can then take place. Molecular and space-filling models provide an insight into the atomic structure of known materials (e.g., salt, plastic, and diamond). The difference in packing and orientations of atoms in lattices of these compounds can then be explained. A short review of magnetism can also be held during student utilization of magnets. Follow-Up Follow-up is conducted by teachers a t the respective school. Upon LSRP departure teachers typically discuss with their students the nrevious presentation, and other areas of science are investigated as teachers continue to build on thescience theme. Students are oftenaskedto write a small written report on the demonstration complete with D ~ ~ u R and S observations. Long-term follow-up by LSRP is the program being in its in the preliminary stages due infancy. Funding Sources Fundinemavcome - . from on camnus sources such as undergraduate and graduate student government. Another source of fundine mav- be from science departments (i.e., chemistrv, -. physics, engineering, biology) a t t h e respec&euniversity. The LSRP was funded by the Community Activities Committee (CAC) and is housed in the Community Programs Office (CPO). Nonuniversity funding is another possibility. Community organizations and private foundations are frequently interested in promoting new ideas, especially those with great potential for growth. Government grants are yet an additional source of funding. Problems LSRP activities tend to be held during regular school hours. Volunteers often have conflicting class commitments, so scheduling of presentations is a problem. This problem was remedied by planning the presentations well in advance and contacting volunteers early in the academic quarter. Inadequate funding also poses a problem. Due to the size of the Latino community in the area, a great educational need exists. As stated earlier, all potential sources of funding, need to be investigated.

Evaluatlon The LSRP is evaluated by (a) teachers and principals of school where the LSRP had conducted presentations, (b) UCLA administrative personnel (i.e., CPO staff), and (c) LSRP nroiect . directors. Followine- everv. .nresentation. an evaluation form is given to teachers and principals of the resnective schools. The comments solicited from these forms are critically scrutinized and discussed among project directors, volunteers, and UCLA adminstrative personnel.

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With the coming of the Zlst century, the demographics of the Southwest and especially California, will be constantly changing. Accompanying these changes will be the additional needs of the settling population that should be considered. T- o meet these needs.. special . sensitivitv and understanding will have to exist. Without careful foresight the region noted will be constantlv.. ~ l a e u e dbv both social and economic prohlems. Nowhere is this more important than where education is concerned. The Latino Science Recruitment Project is a successful program bridging the present and future by understanding the past. School officials, teachers, students, and parents have given much praise for the project. Personally, the joy received and reflected in the eyes of students more than makes up for the time and effort involved in running the program. Science education must begin early in a child's life in order t o foster growth in the science fields. Programs such as this successfully address the issue a t hand. I t is the author's wish that one day a minority national science agenda be created that will promote both scientific education and education in general. In the meantime the LSRP will continue to address the problem, integrating as many aspects of science as possible into the project, by working in both schools and the surrounding community alike. ~

Literature Clted

7. Widnall, S. E. Scirncm 8. Hispanic Business 1988.10 110). 59. 9. Sh&hashiri, B. Chrrnied Demonstrations: A Hnndbook /or Teachers a/ Ch~rnisliy; University of Wireonsin: Wisconsin. 1 9 e Vola. 1.2.

Magnetic Marbles as Teaching Aids Magnetic marhles' are valuable teaching aids for teachers who have steel chalkboards in their classroom, (Those who do not probably can find a portable chalkboard or simply use a piece of sheet steel.) The marhles can he placed around the symbol for an element to show electron dot structures. They are especially useful for showing electron transfer schemes that result in ions with stable octets; the marhles can he moved physically to simulate the transfer of electrons. Further, marhles can he moved until each metal atom has lost all its marbles (valenceelectrons)and each nonmetal atom has a full octet. To simulate covalent bonding (in water, ammonia, and methane, for example), the marbles can be glued to a piece of very Light paper on which the symbol H is written. In that way, enough hydrogen atoms can he moved to complete the octet of oxygen, nitrogen, or carbon. The marhles also can be used to illustrate orbital filling. Just sketch the various sublevels on the chalkboard, and add marhles as the orbitals fill. Use two colors to illustrate the two spin states. A word of caution: Don't place the marhles too close together. Paired marbleswillnot adhereto the chalkboard. Just as electronsmir to form a bond, the paired marble8 sink to a lower energy level (the chalk tray). (Perhapsthe rapid descent of the paired marbles simulates the baired electrons in a superconducting material (?).I Wwk done at Murray State University. Mumy, KY 42071. Available from toy stwes, novelty shops and catalogs, and from Edrnund

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Journal of Chemical Education