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It is annoying to change the font size of equations in a LibreOffice document when you have to do it for a lot of equations because they are not affected by the size of the text. One way of doing this is with the macro below (I got it from superuser.com/questions/290197/how-to-change-the-font-of-all-equations-in-libreoffice-writer).

Sub FormulaFontSizeChanger
    f = InputBox("New font size:", "BaseFontHeight", 9)
    o = ThisComponent.getEmbeddedObjects()
    For i = 0 to o.count-1
        if (not IsNull(o(i))) and (not IsNull(o(i).Model)) then
            o(i).Model.BaseFontHeight = f
            o(i).Component.BaseFontHeight = f
            o(i).ExtendedControlOverEmbeddedObject.update()
        endif
    Next i
End Sub

To use it on LibreOffice Writer go to menu Tools → Macro → Organize Macros → LibreOffice Basic. Then, click Organizer and New... Paste the code above and save. Your macro is created. Now, menu Tools → Macro → Run Macro and find it.

Sometime ago, I fount the paper Learning to “See” Less Than Nothing: Putting Perceptual Skills to Work for Learning Numerical Structure by Jessica M. Tsang, Kristen P. Blair, Laura Bofferding & Daniel L. Schwartz. The paper is not directly related to my research, but I think it is one of the best papers in Mathematics Education I have ever read. Below, I will comment a bit about it.

This is the starting point of the paper:

“Our proposal [...] is that people recruit the distinct perceptuo-motor system of symmetry to make meaning of and to work with integer structure. If true, how can we use this knowledge to help children learn?” (pp. 157).

To answer that question, the authors utilized an experimental design: three groups, each learning integers with a different approach (two common in American textbooks and one emphasizing symmetry). They took a series of measures to ensure the basic premisses of experimental designs (something that is not common in educational research), but what I think makes this paper particularly good is how they defined the null hypothesis. Instead of only comparing the results in a pre and post-test, they used two measures: regular pre and post-tests + a post-test composed of generative questions.

If the results in the regular post-test showed differences between the groups, it would not mean that one of the approaches was better or worst than the others, but it would mean that the quality of the instruction received by the groups varied and this would be a problem in terms of their research question. Therefore, they were expecting similar results in the regular post-test and better performance in the generative questions by the group taught using symmetry.

This was the first time I saw a research using this approach. I think this is very distinctive and improves greatly the quality of the results because it neutralizes the interference of unexpected changes in engagement, excitement, expectations and instruction quality due to simply "being involved in a research project" due to the requirement of similar results in the regular post-test.

Every time I read a paper of a researcher or teacher trying two different approaches in a classroom and simply comparing pre and post-test results, I think: how can I know if the teacher was equally engaged in the lessons? I wouldn't! It is natural to expect that the involvement of the teacher in the research would affect his expectations and performance in the classroom. That is why I think the requirement of similar results in the regular post-test and a second measure to indicate the success of the intervention (generative questions, for instance) sounds very appropriate.

In fact, there are some issues related to the validity of the generative questions, but it is already a step towards more convincing experimental approaches in educational researches directly connected to classrooms.

PS: the paper has other merits beyond what was discussed here. It really worth reading.

References

Tsang, J. M., Blair, K. P., Bofferding, L., & Schwartz, D. L. (2015). Learning to “See” Less Than Nothing: Putting Perceptual Skills to Work for Learning Numerical Structure. Cognition and Instruction, 33(2), 154–197. http://doi.org/10.1080/07370008.2015.1038539

Talvez eu seja processado por isso, mas eu diria que o welsh cake é a versão galesa do scone. Mas o welsh cake não é comido com creme.

O que importa é que ambos são ótimas idéias para um café da tarde ou para um café da manhã mais generoso.

250g farinha de trigo
1 colher rasa de chá de fermento em pó
Pitada de sal
125g manteiga sem sal (fria)
75g açúcar refinado
50g uva passa (opcional)
1 ovo
3 colheres de leite

Misture a farinha, o fermento e o sal. Corte a manteiga em cubos sobre a mistura e amasse, esfregando com as pontas do dedo de modo que a mistura fique com uma textura "flocada".

Acrescente o açúcar. Bata o ovo com o leite em um copo e acrescente à mistura. Amasse um pouco. O resultado deve ser uma massa seca e firme, mas não quebradiça. Acrescente um pouco de leite se necessário.

Coloque a massa sobre uma superfície e abra até ficar com mais ou menos 0.5 cm de altura. Corte em círculos (eu corto com a faca sem me preocupar com o formato, só pra evitar o trabalho de juntar as beiradas no final, abrir e cortar denovo).

O welsh cake tradicionalmente é assado sobre uma pedra quente como se fosse frito, mas sem óleo. No meu fogão, eu deixo 5 minutos de cada lado em fogo baixa numa frigideira de fundo grosso. Você pode polvilhar um pouco de açúcar sobre eles antes de servir (coma quentinho!) ou apenas passar um pouco de geléia (minha opção favorita!).

Rende o suficiente para um café da tarde para umas 4 pessoas.